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My apologies to all of my readers and subscribers. This blog is definitively re-opening: just yesterday we finished operating a bit over 20,000 Rainbow Lipped Oysters for this 2013-2014 Pearl Seeding Season. And this ultimately means that I will –again- have some more time for other activities.

I had all the information ready for this entry since last December but I decided to wait until I could really take the time to write it down with order, this is basically an account of the last important notes of 2013. Without any further interruptions…let’s dive into it!

1) The New “Pearl Fluorescence” video.

This is a re-edit of the video I shot way back in 2008 (with a trusty little Cannon camera) and that has ringed up some 20K visits in YouTube. This new video has HD quality images, as well as new photos and comparisons that may help you to identify or distinguish between many more pearl varieties than ever before. I believe there is no other video on the web with this information available. I hope it helps you in your quest to learn more about pearls.

2) Laurent Cartier of the “Sustainable Pearls Project” pays a Visit.

After years of being in contact by means of Skype and e-mails, we received the visit of Gemologist Laurent Cartier; Laurent is a member of the “Sustainable Pearls” project. This great program is financed by the University of Vermont and the “Tiffany Co. Foundation”, and at present it is working with several pearl farming ventures (including those of my friends Josh Hubert of “Kamoka Pearls” and Jaques Branellec Jr of “Jewelmer”) in order to produce a set of simple guidelines needed to help other pearl farms attain a sustainable pearl culture operation. This would free-up all sustainable-would-be-farmers from the need of a certifier agency (a costly requirement for most farming operations) and having a unified set of criterions that would make it possible for farms with very different oyster species and vastly different environments to work in accordance. This is a very important project, not only for us but for the future of many pearls farms in the world.

During his visit, Laurent had first-hand experience at telling how different are tropical (most pearl farms are in tropical areas) and sub-tropical environments (like ours) when he took some time for a snorkeling tour of our pearl farm…with a temperature of 16 Celsius/60.8 Fahrenheit.

Later, in a photographic session with our Cortez Cultured Pearls, Laurent was able of distinguishing the amazing variety of colors and overtones in our pearls and some pearls were donated to the Swiss Gemological Lab (SSEF) in Basel, Switzerland, were an extensive study on pearls is being carried out to identify pearls by means of their DNA. This is truly a breakthrough in pearl identification, and Laurent is part of the impressive team behind this achievement.

3) The Cruise Ships are Back!

This is something that all of us in the Touristic sector have been eagerly awaiting…the Return of the Cruise Ships. This ray of hope materialized last December with the arrival of “Zaandam” and again in February with the “Azamara Quest” this last February (just before the Tucson Gem Show). It was good to see these magnificent ships back inside the Bay of Guaymas.

The local touristic industry has been suffering since the beginning of this “whole mess” caused by the financial crisis of 2008, the swine-flu scare of 2009 and the “Mexican Drug Wars”. I am not going to go into details about any of these events (that is not the scope of this blog) but I will just point out that I consider that the touristic industry is the best one in the area: local jobs are well paid, small businesses can thrive and many other different economic sectors also benefit. In all: if this industry falls we will have “the real people” suffering too, eventually this cascades into a deeper recession and higher crime rates. Guaymas needs a break…we all need it.

4) Final Thoughts

It is astonishing to see how time just flies! It has been months since my last entry and I again apologize, but I do have to say that these are what you would call “working risks”: I am not just a “blogger”, I am a real “Pearl Farmer” and it is the time you spend at your farm, with your pearl oysters and at the store-front with your pearls and pearl jewelry the one that is truly significant for a business.

Nonetheless, there are some things that we do here that are simply a “Labor of Love” and this blog is one of them. So, I appreciate your patience and your support to this little side project: this is an EDUCATIONAL effort for which we do not generate any income.

So, to wrap it all up: I wish you all a -belated- great and happy 2014 year for you all. Please stay tuned for many more interesting stories and information.

Thank you,


Coming Soon!

Yes, the “seeding season” is almost over, and this means I will be unleashed back unto the world of the living! Er, well maybe not unleashed but at the very least I will be able to write more blog posts.

First off: I need to add “closure” to last year’s (has it been so long?) blog posts about UV fluorescence and the last visitors that honored us with their presence. So, please stay tuned.

Second: things are changing. As much as I love Bob Dylan’s catchy “The times they are a’changing” song, I have to say that there are things that I simply do not like about these changes and that I would like to share with all of you.

So, please stay tuned to the Cortez Pearl’s Blog revival: Coming Soon!

Sunset over Tetakawi

Beautiful view of Tetakawi hill, taken from the pearl farm.

Once again I’m back in the saddle, and after this very hot summer I feel like I am ready to go back to the Pearl Fluorescence series and this actually got me thinking…where else can you obtain a good pearl gemology course like this one and… for FREE??? Been thinking I deserve a position in the Ministry of Education, but then again I’d rather do this for my noble audience: you deserve it and I thank you for reading my blog and for supporting our Cortez Pearls.

In the meantime, let us go back to the heart of the matter and continue with this interesting subject, this will not only help you identify pearls and distinguish them from fake/imitation pearls but also to distinguish between pearl varieties. Last time we touched the subject we had Black pearls on stage, and now we have GOLDEN PEARLS featured.

Golden Fried?

Many people say that “Golden Pearls” belong to a group of colored pearls that range from yellowish to cream/beige and a deeper coppery-gold color, but we can mainly say that true golden pearls are those that are produced by the large “Gold Lip Pearl Oyster” (Pinctada maxima) from the Philippines and surrounding areas. This pearl oyster species is the biggest, with a maximum size of 30 cm/9 inches and with a weight of up to 5 kilos/10 pounds!!! With this great size the pearls you can obtain from this species can reach up to 30 mm in diameter, with the average size usually ranging between 12 and 18 mm (this is not small at all!).

Jewelmer is the Philippine company –led by Jacques Branellec- that grows these impressive marine gems and that has achieved world-wide recognition under the allure of the “Golden Pearl”, a company with an impressive environmental commitment. I can truly say that I admire them for what they have been able to do in the environmental arena and that I do hope we will be able to endure to cause a similar effect upon the Gulf of California: unfortunately, not everything lies in your hands and many of the needed actions fall upon the local Governments; in Mexico we have yet to see a truly dedicated national environmental policy that will join forces with local environmentally-sustainable producers.

One thing that this company has been able to achieve –besides an excellent environmental program and a high-quality pearl- is the color standardization of their gem; this has been possible thanks to a strong genetic selection/breeding program, and in this they have also achieved something that I –and this is my personal opinion, you don’t have to agree with me!- do not like: their pearls end up looking very similar in their looks. I really prefer uniqueness over sameness but we all have the right to disagree.

There is yet another group of yellow colored pearls, but much smaller in size and is grown in China & Japan: the “Golden Akoya”. These pearls are produced from the Akoya-gai oyster (Pinctada imbricata) but this coloration has not always been considered good nor desirable, with most producers going to lengths to have them bleached (under UV light and inside a chloride solution) to make them as “white” as possible. But some of these pearls have a truly nice coloration, such as these natural golden-color Akoya pearls (photo courtesy of Jeremy Shepherd of

Now, for the $100 dollar question: how do these pearls react (fluoresce) under an Ultraviolet lamp??? Let’s check it out!

Golden Under Violet

Here we have two “golden pearls”, but one of these is actually a fake (imitation) pearl. When you look at both pearls it is very difficult to see much difference in their color, but their shape gives them away: the round one is the imitation and the “doll” shaped one is the cultured pearl. No wonder a standardized golden colored pearl can be easily imitated, but this is not the concern for us: Cortez Cultured Pearls do not –and will never, as long as we live- have a standardized color and will always be distinctively unique in their appearance.

Now, let us expose these two under a long-wave UV light and…what will we see???

In the next image we will see 3 pearls: the pair of golden pearls (left: the doll shaped pearl, right: the imitation pearl) and in front of them we have a small white-colored freshwater pearl that I have used before as the “blank” or comparison pearl. The differences between these pearls is actually subtle, except for the little white pearls that glow with a strong blue color.

The main difference between the imitation and the real golden pearl is almost not noticeable in this photo, the yellow color being deeper in the South Seas Pearl but I cannot say it is glowing. I would not use the UV lamp method to identify golden pearls at all. The same is true for the golden akoya pearls, just as we saw in the “White Pearl” entry. There seems to be a pigment or protein in these pearls that interferes with the pearl’s natural fluorescence, and in this way these golden pearls are similar to black pearls.

A Golden Cortez Pearl

This is –after all- the Cortez Pearl Blog so it does make sense to have these unique pearls placed on the same stand as the others, but we have to understand that when we say “Golden Cortez Pearl” you are definitively not saying “Deep Yellow”: these pearls display many other colors/overtones that end up having a beautiful golden-coppery coloration with flashes of emerald green and pink.

What will happen to a Cortez Golden Pearl if we place it under the same UV light? Will the Gulf of California pearl have the same inhibiting pigments as the others? There is no other option than to try the test on both kinds of pearls.

And I do have to apologize for my forgetfulness…I forgot to add in the little white pearl for comparison sake. But I believe that it is more than evident to all that these golden pearls look strikingly different under the very same UV light.

It is quite clear to all that the pigment that is found in other golden pearls is simply absent from the Cortez Pearl. The “Rainbow Lip Pearl Oyster” (Pteria sterna) is a very different species from all other pearl producing oysters, its unique porphyrins can create a very unusual fluorescence.

So, what do you think of this entry? Did you learn something new that will help you to identify pearls? And as always: your comments are important and appreciated, Cheers!

And I want to wish my daughter Samantha and my Uncle Xavier a Happy Birthday tomorrow.

An Unusual Summer

This Summer has been somewhat different to that of previous years. In the last 6 years I’ve used the Summer months to work on writting articles for magazines, travel to sell and promote our Cortez Cultured Pearls, edit some new “Pearl Video”, answer all of my YouTube Channel’s questions and comments and start a new “Pet Project”, but not his year: I’ve been bogged at sales. And Summer is the perfect time to do such things since it is also the time of the year we work little with our pearl oysters, since they don’t really enjoy the hotter water.

And although I still have many things to share with you (I still have the whole UV-on-Pearl series to complete) I have been unable to do so, there have been some things worth mentioning such as this year’s Cortez Pearl Harvest, an event that was recorded by the local newsmedia and TV channels. This was a very special event and unusual because we had some special guests to attend it.

HighCroma HQ (1)


The Annual Pearl Offering

This is our traditional yearly ritual that we perform beforeCosecha de Perlas 2013 (2) we actually begin harvesting our pearls. What we basically do is that we gather all the un-saleable pearls from the previous year’s harvest and we then throw them into the sea. What makes these pearls unsaleable? Their nacre layer may be thin (less than 0.8 mm thick), they may have too many defects or maybe they are not pretty: of all harvested pearls in a year some 60-80% of them will suffer this fate.

Some will argue this is too much, that we should not destroy these pearls…that they are pretty enough, but we believe this is what should be done to keep our pearl from following the path of other producers…we do it because it is the correct thing to do. By the way: the pearls will be recycled by marine organisms, so there is no environmental impact.

When the pearls are thrown into the sea…they just make this really incredible sound that is a delight to listen to! And before the pearls are thrown we dedicate this year’s harvest to a person or group of people. In previous years we’ve dedicated the harvest to the memory of Gastón Vivés, the Yaqui Indian Nation and even to religious imagery (not my cup of tea, but we all have different beliefs and all are just as respectable) such as the “Virgin of Solitude”. This year we dedicated the harvest to the City of Guaymas, hoping for a better future for all its inhabitants. Our guests then release the pearls and we all proceed to harvest the pearls out of the “Rainbow Lipped Pearl Oysters”.

Would you like to be our guest next year?

Pearl Offering 2013


Cortez Cultured Pearl Harvest

Every year I’ve used my different video cameras to film the extraction process of the cultured pearls. Of hundreds of oysters, just a few shots actually make it to editing. This year I used our new photo camera with a macro lens to shoot the video. These shots are usually difficult because we are actually working there (not faked) and there is a constant squeeshing and splotching of pearl oyster liquids and you don’t want these to touch the camera! The oyster’s digestive liquids are specially corrosive.

On this ocassion I was able to obtain some good close-ups, but I do hope next year will yield some better ones. The results can be seen in the video below:

A detailed view of the extraction of Cortez pearls from the oyster’s pearl sac.


Diving with Sea-Lions

Where else can you find Sea Lions (Zalophus californianus) inside a Pearl Farm??? To my knowledge: nowhere else. Most pearl farms are located in tropical areas and Pinnipeds (sea lions, seals & walruses) are usually only found in cold (temperate & polar) seas so you won’t see these friendly creatures in a Tahitian/Phillipino/Aussie pearl farm… dolphins, manta rays, sharks are indeed found in most pearl farms. Back in 1994 there was even a female Fin whale that gave birth very close to the farm…but this was a rare thing. Sea lions are a common sight but we had never before carried an underwater camera to record the event until this year.

We hope you enjoy watching these playful marine critters as they approach our divers and the pearl oysters.


Diving with Sea Lions at the Cortez Pearl Farm

New Markets

For an unusual cultured pearl it is not very easy to move into a new market, but this year I can happily announce that the Australian market for Cortez Pearls is alive & healthy. Australia is know for its large-sized, high-quality South Seas Pearls but as we all know: there is more to life than just white pearls (or black, for that matter). Our Cortez Pearls will be offered by “Raw Pearls” this year and I have to thank Dr. Dyann Smith for this opportunity to open in such a prestigious market.

But this is not the only new place where our pearls will be heading this year…since we have a new buyer in Prague, Czech Republic, so this has been a very different summer for us. Let us hope this upcoming winter season will also be a different one.


Have a Pearl Farmer as your Guest.

Now this is odd. Why have a pearl farmer as a guest in your house? Continuing with my desire to do things differently I –Douglas McLaurin- wish to visit you at your place. Of course I don’t have the time to travel great distances (I do have many occupations) but I can easily visit you at your place in Guaymas, San Carlos and even as far as Alamos. Why? Well, we have always relied on your welcomed visits to our farm & store, but there are people that have already been here and would want to have some time to ask special questions and have some friends to join them in a more relaxed athmosphere…at the farm I am usually bussy so it is not the same: I cannot relax and I have to hurry.

So, if you feel like you would like to have me over to discuss pearls or our environmental protection program just organize a meeting with some friends (with at least 6 guests), call or e-mail me with a possible schedule (I am quite busy, so I would appreciate having some options). I will even bring coffee and tea for you and your guests! Give me a call at the office (221-0136 area code 622 if you dial from another location) or just e-mail me at: info @ perlas dot com dot mx

PMC Coffee Mug Animated

This time we will examine the “opposite” colored pearl group: we’ll move from “white pearls” to “black pearls” and we’ll have a totally different experience in the pearl’s fluorescence. If last time you ended up believing that all pearls glow with a blue color under a long-wave UV light, then you’ll be surprised. But I don’t want to get ahead of myself, let us go out and play in the field.


What is the source for “Black Pearls”?

Authentic "black pearls" –both from the natural & cultured pearls varieties- have been mainly produced by two species of pearl oysters that belong to the "mother-of-pearl" or “Pinctadine” oyster group that mainly includes: the "Black-lip Pearl Oyster" (Pinctada margaritifera and its many varieties or sub-species) and the “Madreperla Panámica” or "Panamic Mother-of-Pearl Oyster" (Pinctada mazatlanica). Some of the characteristics of these Pearl Oysters is their large size (up to 25 cm/9.8” in diameter for the the first one, and up to 20 cm/7.9” for the second one) and they have a beautiful metallic-looking shell whose coloration may range from white to smoky-grey, with flashes of emerald green and violets; once the the shell is polished it displays a beautiful wavy pattern that makes it just perfect for a collector as well as being used to make buttons and all kinds of shell hand-crafts.

These many species of "black lip oysters" have a very wide distribution througout the Pacific Ocean, and you can find them from the Persian Gulf (with the variety Pinctada margaritifera persica) to the islands of Hawaii (with the variety P.margaritifera galstoffi), but it is variety cummingi which stands out for its beauty and large size, and it is in the Islands and atolls of the South Pacific where this oyster is grown for the mass production of cultured black pearls.

Then we also have the “American” variety that we know as the “Panamic Black LIp Oyster” (Pinctada mazatlanica) which was considered as yet another variety of P. margaritifera for many years, but then the many anatomical differences (including the “anal flap”: talk about “dark discoveries”) made scientists conclude this species was unique. This variety is found from the Gulf of California in Mexico, all the way down to Peru and including the Galápagos archipielago and Easter Islands. Below you’ll find a distribution map of several species of Pearl Oysters based on Sohehi Shirahi’s book (Shohei Shirai. 1994. Pearls & Pearl Oysters of the World. Kousoku Printing Co. Ltd. Okinawa, Japan. ISBN: 4-9900287-1-6)

World Map MOP McL 2005 copy (Copy)

The Third Group

There is still another group of marine mollusks that produce “black pearls” and this one is also a group of animals related to the “Pinctadine” group, but different enough: the Black Pen Shell (Atrina maura) and the “Concha Nácar” or “Rainbow Lip Oyster” (Pteria sterna). Since there is no cultured pearl production on Pen shells we will only talk about the “Rainbow Lip” oyster.

The “Rainbow Lip Oyster” is a uniquely different organism: it is related to the “Pinctadines” (they belong to the same family so they are…second cousins!) but this species is much smaller (the largest specimen we have recorded is just 14 cm/5.5”, but on average the “large” individuals measure about 12 cm/4.7”), the shell being less flattened (more concave) and having a very unique anatomy (more on this in a future post): smaller and more muscular. It also has a unique metallic looking shell, and the color range is somewhat more impressive than that of the “black-lips”: it also ranges from a blueish light-gray color to a smoky-dark color with many beautiful color reflections, including green, golden, violet, purple and blue. A photo here can be more helpful.



How we’ve been Trained to See “Black Pearls”

Now, when most people think of "black pearls" they really picture “black orbs” in their minds, but the black pearl is so much more since it can display a enormous variety of colors, from white, to light-gray to an obsidian black color, but they also display beautiful overtones, mainly in green and violet. For the most part you can say that Tahitian pearls display darker colors (black), while the Cook Islands pearl have a more greenish color (pistachio), and "Kamoka Pearls" (from our friend Josh Hubert) and pearls from Fijii have a wide range of rich dark colors. To say "Black Pearl" is almost the equivalent of sayin "Not a White Pearl", but even with all the recent awareness and knowledge about pearls in forums, websites and specialized books there is still confusion surrounding the use of the "Black Pearl" term.

Now, there are many people that talk about black pearls from Japan and China… and the truth is that the vast majority (not to say all) of these so called "black pearls" are actually artificially colored pearls; these have been “blackened” by means of chemical processes (staining/dyes) and/or physical (heating, radiation). Then, these pearls are not black pearls at all and have not been grown in any of the species we’ve discussed on this entry, and it doesn’t matter how much those selling them say they are. In the near future we’’ll show you a way –quite dramatic- to “discover” these crypto-black pearls.

Anyway, today we decided to differentiate several groups of “black pearls” from Pinctada margaritifera (from Tahiti, Kamoka and the Cook Islands), of Pinctada mazatlanica (from Guaymas, Mexico) and of Pteria sterna (again from Guaymas), but also a group of artificially blackened pearls (some Pinctada imbricata from Japan and also some freshwater pearls from China); and something that can be easily appreciated is how these pearls are so different among themselves and this is something that truly distinguishes them from the "white pearls" group that we saw in the previous post.

When we compare these groups we can see that margaritifera pearls are much darker, almost black but with overtones in green and violet (the best quality, as seen in the above image), mazatlanica pearls are more of a dark grey color with some olive green, and that those from Pteria sterna they are very different: highly iridescent. On the other hand we see that artificially colored pearls also display a highly variable appereance (the “Black Akoya” are… just jet-black) and that their Chinese counterparts can be very iridescent, but this is in a “static way”, not “dynamic” in their appearance (will try to explain this in the future).

Here are a few examples:

Panamic Mother-of-Pearl Oyster – Pinctada mazatlanica -Guaymas, Sonora, Mexico.

These include white, light gray and a dark grey-green colors.


Rainbow-LIp Oyster – Pteria sterna – Guaymas, Sonora, Mexico

I see pearls like these every day… and I still find them breathtaking! No need to explain their colors, since it is also difficult to do so.


Artificially Colored Pearls – Akoya and Freshwater pearls.

The Akoya pearl is the one located to the left-front side of the photo below, the other three pearls are all Chinese freshwater pearls and they have been dyed. The colors are static… you can say they are "painted" or “burnt-in” and thus the colors simply remain in place.

Now, let’s see how all these pearls look when they are exposed to a long-wave ultraviolet light… what kind of fluorescence will we see?


Black Pearls under UV

Let’s start with the first group, the "Tahitian" pearls. In the previous post we saw that white pearls glow with an intense blue color, so I will use a white pearl to help us to compare the fluorescence between these two different groups of pearls. This little white pearl –let’s call it the “blank pearl”- is the same for all pearl groups.

As you can see in the above photo, “black pearls” from Tahiti and the Cook Islands and all those that are produced in the Pinctada margaritifera pearl oyster do not possess any kind of fluorescence. Unlike “white pearls” they are inert under this radiation and therefore this test cannot be used to distinguish them from fake pearls or artificially colored pearls.

Will the other “black pearls” behave like this group? Let’s us see…


American Black Pearls

This group of pearls includes those produced by the “Panamic Black Lip” (PInctada mazatlanica) and this oyster produces both light and dark colored pearls so we might see something very interesting: the light colored pearls display the typical white pearl fluorescence, and the dark ones do not show this phenomenon. Somehow this special pearl group is between both the “white” and “black” pearl groups. I wish I had a light colored Tahitian pearl to see if it also displays a similar fluorescence. Obviously the pearls black possess something that does not allow the pearl’s fluorescence.


Sea of Cortez Pearls – Pteria sterna

Now let us move on to the group that is remarkeably different from all other black pearls: pearls from the "Rainbow-lip Oyster" or Pteria sterna. This Oyster has an enormous capacity to produce colors including a “Rainbow” color effect within the pearl (see previous image of the three pearls from this species). Will these pearls behave in a similar way to the fluorescence of “black pearls”? Let’s us see again…

We definitely see something completely out of place in this case. Definitely: these pearls are NOT inert, but neither do the they glow blue… but, instead they glow RED. And this is something diametrically opposite to what we had expected. These pearls are unique in a way that it is possible to use this test to identify them among any other cultured pearl in production currently.


Artificially Colored Black Pearls

Now let us see how fake pearls will behave under UV light. Will they try to imitate the black pearl? Will they glow like the pearls they originally come from (the “white pearl” group)??? Will they glow like Cortez Pearls??? Let us dive into the results:

As you can see there is no fluorescence. All these pearls are inert (except the white we use to compare with). In this sense we see that they behave more like the natural colored black pearl. For those who imagine seeing a small red-pink pearl of the far right: this is actually a “Hot Pink” colored pearl and whe are not seeing any glow from it…just is current color, there is no inner glow. What do these pearls have in them that prevents their fluorescencent glow?

Questions that we will need answers later, but for now I would like to close with a comparison between all these varieties of pearls.


Comparing between black pearls

We see a group photo of these "classmates" and we can easily detect a wide variety of sub-colors, something that we could not observe easily in the previous group (white pearls) and to the extent that we can easily identify the species of oyster that produced it, if you have a bit of experience and you know what to look for.

To the left we can see a large drop shaped “Kamoka pearl” from Tahiti, just in front of it we see a round Japanese Akoya, with a couple of dyed Chinese pearls to its righ, and on the far right a beautiful drop shaped pearl from the Gulf of California. I Just have to add that I somehow forgot to add a Pinctada mazatlanica pearl… a small detail that I hope does not affect you.

Now, let’s look at the reaction of these same pearls under a long wave UV light:

And again we see that only two pearls are glowing here: the little white pearl which is used as blank, and the Pteria sterna pearl with its unusual red colored glow.

We hope that this entry about black pearls has aroused a greater interest in the subject and on the methods used for pearl identification. Next month we will have more evidence and more exotic specimens, so continue learning in this free Gemology course that we are happy to have prepared for our avid readers.

And here we are back in the saddle and readying to continue with the Ultraviolet light test series. Since there are many varieties of pearls to compare I have chosen to separate them into groups based mainly on their COLOR. And why do it this way? because it just seems so simple and obvious, and although many people will say there is not much in common between an Australian South Seas Pearl (SSP for short) and a Chinese Freshwater pearl (CFWP, also for short) –I mean, the differences are jarring: SSP are produced in the sea with a Pinctada maxima pearl oyster, and most CFWP are grown in rivers/lakes/ponds with Unionidae pearly mussels- they have a very similar color and overall look.Assorted Cultured Pearls

Still, each group will have its own sub-group for analysis and comparisons, so as not to cause much discomfort among those that prefer to keep their apples apart from their oranges. So, shall we jump into the tests?


White Pearl Group: Akoya, SSP and CFWP

In this group I decided to include the most common pearls in the World, just with CFWP and the saltwater Akoya pearls you can say you’re reaching well over 95% of the World’s production of cultured pearls. White South Sea Pearls (SSP), which include Australian and Indonesian productions, are far less abundant and larger-sized than its counterparts, but their color is very similar in a silvery white variation. Let us place these pearls next to each other and compare their look:


The similarities in the overall look of the pearls is more than evident, but on close inspection there are subtleties that are revealed: pearls are not like other gemstones and we should not expect sharp, dramatic differences but their beauty is more in the realm of “the little things”. Some can be revealed by close inspection with a loupe/triplet, using a special background and light situation or by immersing them in water (The Water Test). On the photo above you may notice that the pearl on the left (an Akoya Pearl, sometimes called “Mikimoto” or “Japanese” Pearl) has some interesting “stripes” (faint ones, these are the stripes you can see in the mother-of-pearl nucleus; you can see these due to this pearl’s thin nacre coating), that the middle pearl (a Chinese freshwater pearl) has a yellowish-pink tint and the one on the right (an Australian South Sea Pearl) has a greenish tint to it. Some of these features are due to the LED lamp I used to shoot the photos, but they are not as evident in a normal light situation. Anyway, I employed the same light (and distance from it to the pearls) for all this study, so all pearls are subject to the same treatment.

So, how will these pearls react to long-wave UV light exposure? Let us see and compare.


As you can see, the Akoya and Freshwater pearls (left & middle) have a remarkably similar glow (pure white-blue) and the South Seas one (right) has a greenish-blue cast to it. One thing we have to keep in mind for he rest of this series is that every UV lamp, background setting (I recommend a black cloth) and ambience light (a darkened room is best), you employ can affect the results so you may see something different from these results. Finally, these are photos and our eyes are better at capturing the glow/fluorescence effect.


Akoya Pearls


I used 3 different Akoya pearls now to see additional results on this group. I had a very white Akoya, a cream-beige (“golden”) Akoya and a “black Akoya” (irradiated) pearls for this group. Results were quite interesting.


On the image above you will be able to see several things, but first I want to point out the most evident one: a small Chinese Freshwater pearl (CFWP) which I call “the blank pearl” (the “PC” is to be used for Spanish as “Perla China”) and this is something I will do an all UV photos that do not include a CFWP. What for??? It will serve us to compare the standard blue-glow of the “standard pearl” with others. That is the reason you’ll see it there.

Anyway, the white Akoya has the expected color but now we see 2 interesting things: the golden Akoya has a very faint glow –almost none- and it is of an golden-orange color, whereas the “black Akoya” has no glow at all. For the most part fake/imitation pearls display no fluorescence (but I have seen some that do). What does this mean to us? That dyed pearls will not glow the way a pearl does, and that the golden-yellow pigments somehow interfere with fluorescence as well. Interesting isn’t it???


Freshwater Pearls

In this instance I have some traditional freshwater pearls for inspection. I skipped the normal shot because they are simply unremarkable…just plain white pearls. Their glow is the one we quite expected: the beautiful blue glow.


Conclusion & Closing Remarks

White pearls glow with a beautiful blue-green glow under long-wave Ultra-Violet light, but some pearls of the “white pearl” group may not display this fluorescence, this would include some (I can’t say that all until I can check thousands of pearls) of the golden and dyed/irradiated pearls.

What have I missed? I do not have any “Blue” nor “Pink” Akoya pearls for testing, and there are many cheaply dyed freshwaters pearls that I should include in these tests too. I will, as soon as I have samples. If you care to share your personal research or to send me samples I will be more than happy to update this entry to include your personal findings. Please feel free to write to us by means of the “Comments” section.

Stay tuned for the next group: Black Pearls.

Before I start I want to apologize for the long wait… but we have finally finished operating our tens of thousands of “Rainbow Lipped oysters”, and hopefully this means that in a couple more years we will have thousands of beautiful Cortez pearls available for all our customers and friends. It was a both a long (it begun in November 2012) and very cold (temperatures of 6/42 degrees Celsius/Fahrenheit inside the “pearl lab” and of 12/53 degrees Celsius/Fahrenheit in the sea) seeding season, but apparently the operations went well and now it’s just a matter of waiting and of taking good care of our precious little oysters.

Do we have news? Yes we do! By now you know all about our presence in the Christmas edition of the “Bazaar Gilberto 2012” held in Mexico City, of the television program crew that visited last December, but let me tell you about the many other visitors we had: this last February we went up to the Tucson Gem Show, but many Jewelers/Designers also came down from that city to visit our farm, we also had the pleasure of being visited by gemologists from the Gübelin Gemological Lab: Stefanos Karampelas (of Greece) and Pierre Hardy (of France) who are on a quest to find the mysterious origin of the color of our pearls (with a very interesting theory), we also had the visit of Julie Nash, researcher at the University of Vermont and collaborator in the "sustainable pearls" project which has been supported by the "Tiffany Co. Foundation". And in addition to these distinguished visitors we also had the visit of several Mexican and Puerto Rican baseball fans who were at the world famous "Caribbean series 2013" which was held in Hermosillo, Sonora, and hundreds of Canadian and American visitors as well, so in all it was another busy but fruitful winter.

Starting next week I wish to continue with the Fluorescence thread I started on this Blog last year, since I am sure that the subject will be of interest to many of you (because it is) and you will learn new techniques to distinguish between the real and fake (faux) pearls, as well as between different types of cultured and natural pearls.

Also this year we will have an article about our newest designer: Tania Maria of Mexico City, a young woman with great sensitivity and artistic abilities; she made some exclusive jewelry design lines for our Cortez Pearls & Mabe. Unfortunately – and simultaneously fortunately- we cannot share many of her designs due to their enormous success at the 2012 edition of Bazaar Gilberto: out of 10 designs we had we only kept one.

Thank you for your patience and I hope that this year 2013 will provide us all with a a special experience for our senses, but especially in their appreciation of the beauty and uniqueness of the incredible pearls we produce here in Guaymas, Sonora, Mexico.

Shavua Tov! Happy beginning of week for everyone.

This will be a short entry because it is just a comment on the visit made by ​​the production team of British TV company that produces series for a very popular television channel (whose logo is similar to a Yellow rectangle and hint: they have a magazine by the same name) whose name I cannot disclose because I we to sign a non-disclosure agreement, but this particular program is about out-of-the-ordinary farming activities, mainly interesting situations that involve the use of unusual animals that produce out of the ordinary products.

The show’s producer is Nick Patterson and he visited with cameraman Pete Allibone for an intense day of filming that included all the typical work activities in a pearl farm: the cleaning of oysters, the implant/seeding operation, the pearl harvest, diving at the farm, spat/seed collection and the traditional "release of pearls". In short: we were able of compressing four years of work in just one  intense work and filming session of about 12 hours.

This is a review of some of the things that happened during the filming:


Spat/Baby Oyster Collection

The month of December is not the best for spat collection, we were basically inspecting the spat collectors we placed in the bay in the month of September (the collectors are usually left in the sea between 2 to 4 months) and we had previously checked on them and we did not find much seed in them, thus we believed this going to be a problem for the filming, but our brave “Yaqui" workers had something to say about this: "Kiko" and "Zorrito" each found 5 small Rainbow Lipped Oyster seeds (and about 10 black-lipped oyster seeds), so after just a couple of hours of anguish and uncertainty, it had been accomplished and we passed unto the next round of trials.


Diving in the Farm Farm

Despite being in the month of December at the time of the shoot, water temperature had not dropped to what we consider a "normal winter" and we still had a "nice" temperature of 20 degrees Celsius (68 F), a temperature that made ​​Manuel, Enrique and Pete subject to intense temperature changes, since being on the boat under the sun in their wetsuits subjected them to a strong heat and then they had to jump into the icy water… I feel no need to explain how they felt.

Additionally, during Winter, the thermocline breaks due to the strong  Northwest winds and this causes an intense upwelling of the colder, deeper waters, and this in turn causes an intense phytoplankton bloom, thus the  waters of Bacochibampo Bay become intensely green and murky…we usually refer to this as “swimming in cold pea soup”. Pete informed us several times that the shots were extremely difficult to take and that his camera showed terrible visibility (for us, accustomed to these things, we believe that visibility "fair", because when it is "terrible" you cannot even see the palm of your hand when you extend your arm), so hopefully the images will come out okay. Wishful thinking.


The Pearl Seeding Operation

Manuel Nava seeding oystersAh! The delicate surgical operation needed for the production of a cultured pearl: an arcane technical secret protected by Japanese technicians and “rediscovered” by Mexican researchers… an operation that should take no more than 40 seconds to minimize mortality of the oyster, this complex operation will be "immortalized" in this video and I can assure you it will be amazing just because of the amount of detail and complexity that Nick and Pete imprinted on their work: the number of shots and angles will be the delight of fans of the arcane, and I just hope that their video editing work will be able to eliminate the moments when everything was going wrong: when the beads were falling off, when the mantle graft needle did not "grab" the graft-tissue and when something could go wrong it just did.

But al of these problems had an explanation in the technical needs of the shoot: the light we use to illuminate the inside of the oyster was placed in the most appropriate place for the camera and not for the grafter (me), my head was in a position that was more suited of a patient visiting the chiropractor than for one who performs an operation, otherwise the huge HD camera would not have had a clear view to the inside of the oyster.

So, after three hours of continuous shooting they may have be obtained some 40-60 seconds of usable video, but I’m hoping this will result in a very interesting segment… but you will just have to wait until March 2013 to see the final result!


The Pearl Harvest

As you are well aware, we already finished the 2012 pearl harvest and therefore we did not have any pearl oysters ready for this event; so it was necessary for us to harvest some oysters that had to be harvested until the summer of 2013. We obtained a few pearls of great beauty and amongst these a beautiful dark purple pearl. This is perhaps one reason why this program wanted to film here in Guaymas and not in Australia or Japan or China: because the color of our pearls is totally different from other pearls productions and this is something that is sure to amaze those who think that pearls are only black or white, or in short to something like 95% of the public (but not to you, faithful followers of this blog) that these TV producers hope to have for this program.


The Pearl Release

I’ve just given this name to this “annual event” because I could not think of a better way to explain it in short, but this event happens just after the harvest of pearls, and what we do is simply take all the low quality pearls and –instead of selling them- we throw them all back into the sea (in a preselected, deep area of the bay, I’m just making sure you know this so you will be discouraged to look for them), there they will be "eaten" by nacre-eating bacteria (recyclers) who will release the pearl’s chemicals back into the water, where they will once again become available for other marine organisms. This is our way to avoid low-quality pearls from reaching the market, we do not cause ourselves any embarrassing moment and we avoid any temptation, ensuring a risk-free future for the Cortez Pearl: for us, pearl quality and value is essential, not optional.

Usually, the release of these pearls is carried out in a sort of ceremony, so we individually "dedicate" this event to a given person: this year we dedicated this event to all the brave Yaqui Indians that in times past gave their lives in the pearl fisheries, and also to the little oysters that produce our pearls and allow us to earn our daily bread and finally, to all our blessed customers, the people who put their faith in our quality and appreciate the unique beauty of this Gem. For this video shoot, the ceremony was entirely visual and we had to release the pearls at sunset, from a rocky cliff on the coast, where we were trying to avoid falling. This was definitively the most dangerous of all video shots.


As the Sun fell…

After a busy day of work on the farm and with a heavy fog that hung over the bay, Nick and Pete were preparing to take time-lapse shot of the sunset over the majestic hill "Tetakawi", but the thick fog left us totally immersed in an other-worldly gray mist; I’m sure this made our intrepid Londoners feel quite at home. The truth is that I had all but given up this time (absolutely NOTHING could seen farther than 100 feet away) but this intrepid pair sought ways to find the sunset and they did: a small chink of light appeared on the horizon and they achieved some beautiful shots.

Then it was time to say goodbye amid beers at a local pub, Nick and Pete showed us some of the photographs they took at the farm and many of the shots really amazed us with their quality: some artists really are at good at what they do, and have an amazing professionalism and vision that makes them truly worthy of the "Yellow Rectangle" brand (I am not saying they work for this brand, I’m just equaling the quality of their work to that of the implied brand…ok? But I’m not saying it is not…I’m not saying anything!).

We wished these artists a good trip back home, and we were left with a series of experiences and emotions. Maybe something that really catches my attention is just how many people around us were excited and surprised saying: “Did this TV program really came just to visit the Pearl Farm????” And when Nick Patterson asked where they came from (their trip was from London to Los Angeles and then to Hermosillo and finally Guaymas) and if they had really just come to visit us… this mind-boggling for some. Another thing that apparently caught everyone’s attention was Nick’s comment about the the view from my office and how it is much better than the one in his London office: It’s true, our Bacochibampo Bay is amazing in its natural beauty.

What I can say? Not much, just that our “world” is accustomed to assign value only to the things that have been massively publicized in the media and that have received an injection of millions of dollars, and against this mentality is hard to do anything, but perhaps this bit publicity will help us to achieve some greater regional acceptance; this is something we have not been able to achieve locally: can we become prophets in our own land? Only time will give us the answer…


Final Remarks

It has taken me more than 4 weeks to finish this entry. We are in the middle of the pearl seeding season so most of my time is spent at the farm so I have to apologize for the terrible delay in delivery, I do anticipate more delays since we will continue this crucial procedures and we will also be going to this year’s Tucson Gem show…so please bear with me.

See you soon!

Well, we are back from Mexico City and the 2012 Edition of the “Gilberto” X-mas Bazar, it was a long and strenuous week of work but very fruitful. We hope we will be able to do next year’s edition and fortify the relationships we’ve forged this year. By the way: we did something we were NOT supposed to do (ever!) but everything was just peachy: The three of us traveled to Mexico City on the same plane, together. Period.

The thing is that we had made a promise –years ago- to avoid being together on airplane and car trips, this in order to minimize the risks of having all three of us perishing in an accident and leaving our Cortez Pearl Farm as a poor orphan…what would happen to the farm? Who could take care of our oysters? Who will seed them? Fortunately for us and for our 120 thousand smiling little oysters: we came back, safe and sound.

Anyway, I am writing a full account of the “Bazar Gilberto” event in our Spanish Edition of the Blog, but I will not re-write it in English. But if you are interested please let me know and I can surely change my mind. At present my mind is up for a re-writing of the famous “Pearl Fluorescence” video (with almost 17,000 views on YouTube), so we have new photos, more details and a much better video; I guess we are off to a good start!


Pearl Fluorescence

Mineral Fluorescence - Wikipedia

What is Fluorescence? Simply put: you can see it when something emits a glow. Many minerals display this attribute, specially when exposed to Ultraviolet light (a form of radiation that is invisible to our eyes) and the way they glow –I’ll call it fluorescence from now on- can be unique and can help to distinguish from one substance/material to another. In gemology it is very useful to distinguish between real (cultured & natural) pearls and fakes/imitations.

In the case of pearls, the light you must use for this test is a Long Wave Ultraviolet lamp. Short wave lamps just don’t have what it takes to make this test work. If interested in buying one of these lamps I can recommend a fairly inexpensive LED light that can become your pearl’s delight and even your children’s favorite “camping toy” (Warning: Never, ever, allow anyone to look directly into the light!), since it can help you find scorpions at night (yes, some life forms also fluoresce!). This is both fun and scary, since on one occasion I realized we were surrounded by several dozens of these desert denizens and spent a rather sleepless night.

UV lamps

Anyway, you won’t be disappointed in the versatility you gain by purchasing one of these inexpensive UV lamps: you can find scorpions, mites, blood stains and even make your pearls fluoresce. Now that you are well equipped, let’s go and use the lamp!

Shine on You Crazy Pearl

I don’t really care for diamonds nor for many other gemstones… they are not “my thing”, but I can go crazy over all types of pearls (and I also enjoy all types of Opals and Amber) and this is what actually happened when I started taking some photos of pearls under long-wave UV: I went into a “Pearl under UV” frenzy… I photographed as many pearl varieties as possible under long-wave UV just to see the reaction of all these pearls to the fluorescence test. I do hope you will find the result interesting if not fascinating.

And of course, I cannot place all the results here at the same time, so I will produce several short posts with the results and a discussion, and we’ll have some less traditional pearls to test, such as: Abalone, Clam, Conch & Marine Mussel, as well as the whole array of Cultured Pearls (Akoya, Freshwater, South Seas and Tahitian blacks), Mabe Pearls, Fakes/Imitations and even some Natural pearls. Some of these pearls have very interesting reactions to long wave UV so keep posted.

In the meantime I leave you with a taste of the fun we will have with this test…a found this little critter in one of my work-boots last year. I keep him in my office as a good luck charm, and here we have him “hugging” (to the left) a freshwater pearl and to the right a Cortez Pearl.

Alacran con Perlas en UV (4)

Anyway, be safe and always look inside your boots before you wear them on!

BTW: This little Desert denizen –and the pearls- are glowing/fluorescing thanks to the use of our UV lamp.

For us here in the Sonoran Desert it is a time in between seasons that most people know as “Fall” or “Autumn” but that for us desert-dwellers just means “Summer is Over”. Most people in the area just consider we have two yearly seasons: Summer and Not-Summer. Spring and Fall just last about two very pleasant weeks each, so I do have to agree with local wisdom on this one. Also gone are hurricanes, and I do want to take the time to express my heartfelt condolences to the people that have been affected by hurricane “Sandy” throughout its destructive path in the Gulf of Mexico and into the Eastern coast of the United States of America.

And now that Summer is over we start to experience a couple of environmental changes that make the Sea of Cortez such a unique ecosystem, and that for those that have not experienced this may come as a surprise: the Gulf of California is a Sub-Tropical sea. And this basically means our waters are placidly warm during summer (local high temperature in Bacochibampo bay is 32 Celsius/89 Fahrenheit) and somewhat cold during winter (local lows are 12 C/53 F), and thus our environment changes dramatically from Summer to Winter, the Gulf becomes a different entity because:

1) Summer months: water temperature rise and water becomes clearer, with a dramatic drop in turbidity, this is due to a lack of strong winds. Winds are also responsible for turbidity and for the mixing of bottom nutrients (upwelling), which in turns causes the great algal blooms that enhance this turbidity. This is a great time to SCUBA dive or snorkel in the area, since you don’t have to use a wetsuit and you can spend quality time in the water.

2) Winter months: the strong Northwestern winds begin in November, causing massive upwelling and algae blooms, the summer thermocline breaks and releases deep, colder water. Visibility decreases to the point where you cannot see your hand if you extend it away from your face. Adding to this is the lowered temperatures that make it hard to stay inside the water for periods over 20 minutes, unless you use a wetsuit. Red tides are also common at this time of the year.

Enrique Scuba DivingAnd in the process of preparing for this dramatic environmental change we have just received two full sets of SCUBA diving gear that will allow us to continue working underwater during these months. Both of these have been secured with the help and support of the Sustainable Pearl fund, and will be used for our normal farming operations and in order to continue our environmental studies in Bacochibampo bay, helping us to monitor the local pearl oyster and sea-cucumber populations.

And this is important because most local fishermen are less capable of fishing during winter and we can actually see a more natural behavior in the population dynamics. During summer we may have a fishermen visiting and destroying an entire population, finishing up months of work.

Fishermen inside the pearl farm's area of influence

I do have to mention that –at present time- it is impossible for us to prove that the work or research we do as part of our commercial operation is actually causing a measurable positive effect on a grand scale, we believe the efforts are indeed having a positive balance –based upon our experience- on a local scale: the local populations of Black lip oysters and Sea Cucumbers are dramatically higher than those of previous years, but this information has already been covered in this Blog so I won’t give you this information yet again.

What we are gaining is a better understanding on population dynamics: why are some years better for reproduction? why did we have a large die-off? did something eat the oysters or was it the environment? Many of these questions can sometimes find an answer when a photo or video (taken with the HD Pro Camera purchased for this purpose) shows you a large 20 arm “Sun-Starfish” on top of a cluster of pearl oysters, or when a fisherman is seen capturing some sea-cucumbers.

Without the diving gear and the camera we would never have the answers, which in turn lead to more questions that require answering. In all, this is a race against Time itself: since Humans have been given a limited time to live and we have a such a small time-frame in which we can actually do something to learn from Nature, specially in an Environment we were never intended to live in.

Hopefully, and with the continued support of the University of Vermont & the Sustainable Pearls project, we will be able to gather more information and help future generations in the quest for sustainability.

Bacochibampo Bay: Summer vs Winter

Sustainability Goals

The project we initially proposed to evaluate our pearl farm’s sustainability had the following goals:

  1. The evaluation of the pearl farm’s environmental effect on the local populations of native pearl oysters (and other species) and recovered oyster beds as niche-ecosystem.
  2. Local fishermen will support the pearl farm as nursery (refuge) area of commercial fish species. This will aid in improving long-term viability of artisanal fishing livelihoods in the region.
  3. A communication campaign about the success of the project, in conservation and socioeconomic terms.
  4. The lessons learned from the ecological evaluation and monitoring, sustainable practices, pearl-oyster technology and any associated activity of the pearl farm will be provided for the development of criteria and standards to evaluate pearl farms. This will feed into a feasibility study for the certification of pearl farms.
  5. The pearl farm -and its perimeter- is under way to be legally considered a wild-life refuge zone where fishing is not allowed, only pearl culture would be allowed.

Unfortunately, we have been unable to secure the funds to carry this out this research that has several benefits to our local environment and to the fishing communities too. Oh well! It’s all about politics in the end and we are not –and will never become- politicians and this –of course- reflects on our inability to secure support. I guess we will just continue to do things our way for the years ahead…which is not a problem but things just move at such a slow rate.

My next entry will be about the “Bazar Gilberto” event we had in Mexico City, and the new jewelry styles that will be available from the “Sea of Cortez Pearl” jewelry store. See you soon!