There are a number of precious or non-precious stones that can be considered toxic due to their chemical content..

Poisonous when it is raw ... or its dust is poisonous when it is broken, manufactured, or placed in the mouth...
When polished and ready into a ring or pendant ... it is safe
These stones contain arsenic, lead, mercury, and other toxic substances..
It is preferable to wash hands after touching them when they are raw...
Some flint stones emit harmful rays
Artificial radioactive stones such as artificial phosphorous balls .. There are no natural phosphorous balls..
Dark synthetic quartz is almost black
Natural and artificial colored diamonds have harmful rays
The ancients, especially kings, wore emeralds and coral, as the prevailing belief that emeralds and coral are anti-toxins...
These are some types of toxic gemstones:

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