NO expert but I read somewhere that you can chip a piece of waterever off then boil it in some water. Then after the water cools to say room temp. Put an experimental fish in it and see if it survives. The fish should be one that is very "delicate" like a canary in a mine. Boiling the water concentrates whatever might be coming out of the stone in it. Like I said, I read it somewhere so I don't know how accurate this is but seems logical.
Posted on Oct 7, 2005, 11:00 PM from IP address 170.109.248.2