Water does nothing at all to pearls. After all, they grew in the water...
The problem is the silk used for stringing; if it doesn't dry quickly, it can rot, and as you can imagine it's easy for the part of string that is inside the pearl not to dry completely for a looong time. The silk can look dirty for a number of reasons, not least that silk tends to stain when it's wet; restringing is not expensive.
Incidentally - while I share the advice on fruit juice and vinegar (acidic substances that can dissolve the aragonite in the pearl), the advice about detergents is vague. Washing up liquid is just fine; products containing bleach, enzymes or other oxidizersu (powder detergent for washing machine and the like) may affect the colour, and acidic products (limescale remover) are dangerous.
I found reading this very interesting. Where i got my current wedding ring resized, i get free cleanings on all my jewelery. I have a very unique pearl ring that was my mothers, that she had basically all my life, and was left to me when she passed in 08. Anyways, everytime i go there, he says "Well this is a pearl that's obviously been worn and damaged in water" It is highly offensive because i've been there several times, and he always says this, and i always have to mention it is a 20 year old ring.
So does water really bear no ill will to pearls?
colored diamonds
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