# Removal of precious stones before the use of nitric acid



## frank99123 (Apr 1, 2016)

Is there a need to remove precious stones when dissolving the silver into nitric acid? Thanks for any replys!


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## nickvc (Apr 2, 2016)

Some precious stones such as diamond, ruby and sapphires are usually fine to leave in the settings and recover after treatment others such as emerald and opal need removing first if possible as the acids can really damage them.


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## upcyclist (Apr 4, 2016)

nickvc said:


> Some precious stones such as diamond, ruby and sapphires are usually fine to leave in the settings and recover after treatment others such as emerald and opal need removing first if possible as the acids can really damage them.


What Nick said. Keep in mind that any inclusions might be something "not sapphire" (for example), and any surface-reaching inclusions are then a fast-track for the acid to get to the inside of your stone. On the upside, you'll definitely know which stones were dyed and/or stabilized! 

In general, leaving the stones in won't hurt the solution, but it might hurt the stone. If we're just talking melee/quartz family/etc. that you don't care about, just filter them out later. If you're only refining sterling, you could filter them out before dropping silver chloride or cementing. If you're refining gold, you could filter your AR before precipitation for gold.


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## NobleMetalWorks (Apr 4, 2016)

I remove rubies and emeralds, or oily stones. Where the inclusions, specially in emeralds, contained a water solution during formation and has since been treated to displace the water solution with an oil. 

If you try to process certain stones in nitric or any other acid, you run the risk of displacing the stabilized inclusions which could cause the stone to crack and even break.

Best practice is to remove all the stones you can, regardless of what they are. The tiny ones you cannot remove are not generally worth very much. Stones might change color, or take on solutions in inclusions where the color of the solution could change the color and quality of the stone. And if the solution is gold, even if it's tiny amounts you are loosing you could also loose gold as it could be trapped in the inclusions.

Scott


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