What kind of water do pearls contain?

[Monyettes]

This might be a silly question, but it just hit my mind. I know pearls contain some water, but is this the water from the sea or lake where they are farmed or do they produce ”their own” water?

 

[Pearl Dreams]

Interesting question.

The oyster or mussel consumes food in its watery environment, and then produces nacre from its own body, of which H2O is part of the structure. In other words, water is water.

But is salt part of the structure of the nacre, if the pearl forms in a saltwater oyster rather than a freshwater mussel? I don't know. I have not read that it does.

I think I need to read more about the structure of nacre.

 

[ericw]

As Pearl Dreams says, "water is water".
Any organic tissues always contain water (that's the fundamental element earth environment offers to build the life), and this water always contains a bit of salt itself, but an amount without relation with living environment. For exemple, flesh of saltwater fishs doesn't contain so much salt than the water where they live. It's probably the same for oysters tissues, and their pearls.

 

[BWeaves]

I would think that any H2O in a pearl comes from the mollusk, just like any H2O in your own nails or hair comes from your body and not from swimming in a pool or taking a bath.

 

[ericw]

I would think that any H2O in a pearl comes from the mollusk, just like any H2O in your own nails or hair comes from your body and not from swimming in a pool or taking a bath.

BWeaves, each kind of living organism has its own process to absorb water it needs (water is never a production, it's already first in nature). We drink to do that, but, for exemple, vegetables, bacterias, and many lower organisms absorb water through their "skin" bathing in water or humid areas. that's probably the case of oysters and mussels. Then, mollusc uses this water to build nacre and any other parts of its body.

 

[BWeaves]

Thanks, Eric. That's exactly what I was trying to say. You said it better than I did.

 

[ennui]

I've been told that pearls can be affected by humidity or lack thereof. I believe pearls should not be kept in bank vaults because the air is too dry. And they do seem to absorb moisture from being worn.

 

[Pearly-Pearly]

I also understand that the skin oils are good for pearls but always thought this could be part of the reason older white pearls have a patina.

 

[ericw]

Pearls need a bit of moisture, but not more or less. Conchiolin, the cement of aragonite crystals of pearls, is a protein we can compare to the one making nails and hairs (horns too), mentioned by BWeaves. Then, we may better understand how moisture works on a pearl. Too much moisture softens conchiolin, damaging its cement properties, and dry makes it fragile, for the same result.
Any kinds of oil must be avoided: oil can change conchiolin structure, and worst, can enter between aragonite crystals layers, all of that killing luster of nacre.

 

[ennui]

I've heard that mineral oil is okay -- read it on this forum, actually. https://www.pearl-guide.com/forum/showthread.php?4287-Mineral-oil-and-pearls

 

[ericw]

I've heard that mineral oil is okay -- read it on this forum, actually. https://www.pearl-guide.com/forum/showthread.php?4287-Mineral-oil-and-pearls

Sorry, ennui, I have a doubt: in true, most oils have a complex chemical composition. Often they contain some essences, even a little bit, and other chemical not good for pearls. It's like water, often naturally acidic or artificially containing bleach, hazardous for pearls too, but not for other regular uses. Personally, I wouldn't take the risk to use these oils on pearls.