The chemical statement was me quoting another member Brian .
To answer your question is not much at all and needs to be old stuff . This new has very little in it .I wish I had weighed just what it took to
get 6 oz. You stockpile then extract and then just keep adding to your bead till you get enough for a chunk .
The schools here give me their old PC's but it's really more work getting what I work with out than I get back but is just a hobby .
That does pay after awhile . Intel 486 CPU's are where you can do good but are hard to come by . They sell em on e bay for more than you can get out of them