Treatment of White South Sea Pearl

[cookierookie]

By the way, I followed Jeremy's instructions and pricked one of the pearls I purchased in the philippines with a needle and it left a mark! It's coated! Just thought that it would be interesting to note.

Other than the needle test, is there any other way to test if a pearl is coated?

 

[Sutrisno]

Hi Val,

Can you take a picture of the pearl having left a mark? I have never seen one in my life actually...

 

[cookierookie]

I'll try! I'll use the biggest needle so that it's obvious enough. I also scratched the pearl with a needle and it also left a mark that could not be wiped off. According to my understanding a simple scratch should not leave a permanent mark on a pearl, right? Not unless it runs out of nacre and the nucleus is exposed.

Will post pictures tomorrow!

 

[pattye]

Val, yes, a simple scratch will indeed leave a permanent mark on a pearl. It doesn't have to be scratched clear to a nucleus in the case of a bead nucleated pearl. Many freshwater pearls are tissue nucleated, and have very thick nacre.

 

[cookierookie]

Hmmm...then how is it different from a prick of a needle? Jeremy was telling me via email that if you prick a pearl with a needle, if it is coated it will leave a mark. I tried pricking and scratching (with a needle) a few crappy pearls I have here, the needle left a mark on the white SSPs, but did not affect the dyed golden SSPs.

Can Jeremy enlighten us more about this?

 

[cookierookie]

Hi all,

The mark from the needle on the pearls are too small to get on my very ordinary digital camera...

so instead of going upclose, I might as well upload some specimens of pearls in the quality that is commonly sold here in the pearl markets. From the pictures can anyone enlighten/take a wise guess what treatments they have gone through? that would be really helpful!

Pattye: If a scratch would leave a mark as well...wouldn't that make my experiment completely useless? if a scratch will surely leave a mark, surely a prick from a needle would too then, right?

 

[pattye]

Val,

This experiment likely would be affected by the instrument used to prick or scratch, and the amount of pressure used. Also what is seen by the naked eye as opposed to viewing with a loupe may be different.

In your first photo, there appears to be a small approx 2mm scratch on the upper left pearl that is fully shown~is it one you made? However, there is nothing I notice in the pics that would make me feel these pearls were coated.

 

[cookierookie]

Val,

This experiment likely would be affected by the instrument used to prick or scratch, and the amount of pressure used. Also what is seen by the naked eye as opposed to viewing with a loupe may be different.

In your first photo, there appears to be a small approx 2mm scratch on the upper left pearl that is fully shown~is it one you made? However, there is nothing I notice in the pics that would make me feel these pearls were coated.

Hi Pattye,

Under a 10x loupe, would I see anything different if a pearl is treated? what would it look like?

and yes, the scratch I made with a needle is about that size and is shallow, like the upper left pearl -- though i'm not sure if that is the pearl I scratched because I mixed it up together with other pearls.

 

[jshepherd]

Poking a pearl and scratching are two different things. You shouldn't be able to poke a pearl with a needle and leave an indentation. I don't have a lot of experience with coated pearls, but this was a simple test described by Elisabeth Strack at one of her Tucson lectures.