Amethyst, Pyrite and other rocks in a tank?

I have some big chunks of amethyst, pyrite (fools gold) and some other neat looking rocks, can I add them to my freshwater tank?

 

Hello Kimoore,

Check out the links below:




Ken

 

Hello Kimoore,

Check out the links below:




Ken

thank you!!!!

 

Anytime!

Ken

 

I have used amethysts ( and other quartz) for years in tanks, as well as the different beryl crystals ( emeralds, aquamarine, topaz, ect).
I would be leery of the pyrite, due to its occurrence with other metals.