How Do I Clean A Piece Of Amethyst?

[ZephyrStarPlaties]

I have a little peice of a geode that has amethyst in it and I thought it might be cool in my tank. How should I go about cleaning it? I'm a bit worried about boiling crystal, but if someone here has tried it, let me know.I'm not even sure if it would be ok for the fish.

I also have some quartz, if that would be safer.

 

[DrRob]

Don't boil rocks. Any air pockets in them could explode. Toothbrushes are good for cleaning rocks.

There's a post here

http/www.fishforums.net/index.php?/topic/55806-rocks-for-use-in-the-aquarium/

that's quite useful. Basically you need to worry about sharp edges and minerals in most rocks.