What makes a baroque pearl barouque?

[Casey.R]

as opposed to an odd shaped freshwater pearl? Is it because they are saltwater?

 

[jshepherd]

If this question were easy to answer we would not have any more baroque pearls!
There are a lot of theories. Some say it is because the nucleus gets loose and moves around the gonad, others think it is to the whim of the oyster. As techniques are improving fewer baroques are being produced, and none of them are intentional.
Freshwater pearls can also be baroque. Baroque pearls are simply pearls without a symetrical shape (if sliced from end to end). Because freshwater pearls do not have a bead-nucleus, baroque shape is very common, much more so than the common drop or circle shape of Tahitian pearls (commonly referred to as baroque - incorrectly, but accepted).

 

[CortezPearls]

I do not concur with Mr. Shepherd: we know the reasons why pearls come out in baroque pearls (for most cases), altough it is not possible to stop them from coming out in this way...for plain commercial reasons.

Most of the time, a baroque shape occurs during the first stages after the seeding operation, when the mantle piece (graft) is beginning to form the "pearl sac". If there is a mild bacterial infection you will get a small "bump" or "crinckle", but if a major infection happens you will have a large amount of gas produced by bacterial action and the pearl sac will deposit conquiolin (protein) that will expand around the "gas bubble". Eventually being coated with nacre, you will obtain baroques shapes or the notorious "Giant Gas Pearls" (huge pearls, full of foul smelling liquid). One of the reasons why some SSP producers began using antiobiotic coated nuclei was to lessen the amount of infections, thus decreasing baroque shaped pearls

Also, for the pearl to become perfectly spherical it must rotate freely inside the pearl sac (in all directions), but due to tissue constraints (another organ, a muscle, etc.) the pearl will not be able to rotate at all...then you get a baroque. Different shapes are obtained with variations of this: teardrop-pearl rotates freely at the beginning, later spins only on one axis, etc.

Finally, you have TIME. A very important factor. We've seen that if you grow the pearl for a short period -let's say: 4 months- it will be Round shaped about 95% of the times. BUT, if you grow it for a longer period -let's say: 20 months- it will be Round only 10% of the time.

Obviously, this has a profound impact on quality:
A)short culture=mainly round shapes=thin coated pearl.
B)lenghty culture period= more baroque shapes=thickly coated pearl.

There are many other considerations to take into account (oyster variety, seeding technique and tecnician, environmental conditions, etc.) but these are what I consider to be the 3 main reasons for baroque shapes.

Douglas Mclaurin

 

[jshepherd]

I would also like to point out that Akoya producers also use antibiotic coated nuclei now as well.

 

[KAC]

I can also confirm that the Chinese are treating mantle tissue with an antibiotic prior to insertion. I believe I have a picture of this, I'll post it if i can find it.

 

[CortezPearls]

Mantle tissue has been "treated" with antibiotics since decades...even before antibiotic use was widespread mantle pieces were treated with Merbromin solution (Mercurochrome Tincture) for 2 reasons: as an antiseptic and to better visualize the mantle.

To me, the use of antibiotic coated nuclei on Akoya is something really new. Thanks for sharing this info...could we say it has become a standard procedure now??? How long has this been taking place???

Thanks for the Information...it is great to share knowledge.

 

[jshepherd]

It has been going on for quite some time. The nuclei are soaked in a liquid solution with antibiotics prior to the insertion. I was under the imression the Japanese have been doing it this way for years...

 

[CortezPearls]

You got it right entirely...it is the way it has been done for decades: dipping the nuclei inside water with antibiotic.

My mistake, I was trying to talk antibiotic coated nuclei...these are usually thickly coated with yellow-colored tetracyclin antibiotic (wide spectrum). In this case, the beads are packed in vacuum sealed plastic bags (0.5 Kilo) ready to be used...no dipping involved. Must be used right away whenever possible. Maybe other antibiotics are being used now as well. Read some papers that these actually help reduce baroque shapes by about 30% in some instances.

I don't personally use these...don't like the idea of creating resistant strains of "SuperBacteria".

Douglas

 

[jshepherd]

That is definitely not the way it is done in Asia - especially in China. The nuclei are packed tight in burlap bags and 5 gallon buckets until they are ready
One thing that always amazes me is the way they sit down for 2-3 weeks on end and examine every nucleus to make sure the quality is high enough to use for nucleation. Then, if a pearl came out poor, they strip the nacre, repolish, and use it again. A lot of work for those little things!

 

[KAC]

You got it right entirely...it is the way it has been done for decades: dipping the nuclei inside water with antibiotic.

For those members that don't have the ability to actually visit a pearl farm, here is a pic of a technician getting ready to insert a nucleus after dipping it in antibiotic.

 

[CortezPearls]

One thing that always amazes me is the way they sit down for 2-3 weeks on end and examine every nucleus to make sure the quality is high enough to use for nucleation. Then, if a pearl came out poor, they strip the nacre, repolish, and use it again. A lot of work for those little things!

That is quite a lot of work...most Aussie producers will do the same to their nuclei, but when you are talking about beads that measure between 16-22 mm it is quite understandeable (large nuclei can even be sold individually, and cost at least $100 USD and sometimes more).

Mr. Shepherd: Are they using Bironite beads in Chinese Akoya?

Regards,

Douglas

 

[jshepherd]

I do not think anyone uses byronite in China, and I have not heard of it in Japan either. The cost is just so much higher, I think only producers of larger pearls such as the Tahitians are using it. Most Chinese prefer the Chinese shell for nuclei, and it is now it is used a lot in Japan as well (Mississippi shell is getting more scarce/expensive).
Do you use any byronite in Mexico? How is it? Does the hardness work well with nacre?

 

[CortezPearls]

We tried a small sample of Bironite from an Aussie supplier...larger beads (2.5 bu) than those we usually use on our Rainbow Lipped Oyster so we were not able to gauge them appropiately. Still, we tested them: dropped them, slammed them against a hard surface, drilled them, heated them, etc.

They are really good: drilling tests were excellent! They never chip nor crack nor separate (you've seen it: the nuclei just breaks apart, usually at a protein layer). But, they are still expensive.

Still, it is good to have an option...specially if the mussel fisheries are closed in the future or environmental changes affect mussel populations. You can never tell.

Douglas

 

[jshepherd]

Did you try heating the pearls that had the byronite nucleus? How is the density (2.8g/cc)? This is one of the problems with the Tridacnae nucleus (that and it is a protected species).

Have you read anything on 'Vapor Encapsulation'? If this new process is a success I think that quality nuclei will no longer be a problem as even 4th grade will look like first. I guess this really only matters to Akoya producers, but in the end it would help everyone, and improve the overall quality of Akoya pearls in general.

 

[Richard W. Wise]

Douglas,

Have tried to follow the development of cultured black pearls from Baja but have not seen them now for several years. Are you set up in Tucson?

I would, for one, be very interested in and update on how you and your farm are doing. One image you posted in another thread seems to indicate that the quality of the production has improved since I last saw it. At that time, several years ago in Hong Kong, the pearls were small, misshapen and seemed to have a brown overtone. The one in the image has a beautiful orient, tell us more.

 

[Caitlin]

Douglas

Are you coming to the gem show? Please let me know where and when you will set up. I have yet to see some Cortez pearls of any size over 3mm in person. I'll come look and write you up a review for this forum.

Is any one else going to be there?

 

[pearltime]

I'm planning on going to look over the goods.

 

[pearl guide]

test-please ignore

 

[nlerner]

Barroca

Barroca

Well, the baroque style in art which was rich in movement, color,curves and gold came to express the needs of the Jesuits.
This style was named after three possible sources;
1. Two brothers, carpenters by the name Barroci, (in Italy) who were famous for their wooden curves in furniture.
2. After the amorphic shape pearl, the barroca pearl.
3. After the 'peruke' German name for the very curly and fashionable wig.

nora

 

[Zeide Erskine]

Hi,

I go with number 2. Number 3 is way off the mark since the German word "Per?cke" just means wig of any kind without prejudice to style. As later the Art Nouveau style, the baroque period was emphasizing natural shapes.

Zeide