bc.gold 3,403 #1 Posted June 7, 2020 (edited) This below is what i salvaged from Jack's scrap pile yesterday afternoon. The connectors in the top images are gold plated, the fingers on the daughter cards are also gold plated over a nickle barrier to keep the gold from migrating into the copper. Cut the gold fingers off along with the connector pins, gold is a soft metal which easily abrades from the source in a rock tumbler, rinse the parts off with water through a coffee filter. The powder once dried will have the appearance of cocoa powder, bundle up the filter paper with the gold powder inside then melt the powders into a button which will now have the beautiful lustre of 18/22 karat gold. When your melting the gold no flux is required. The older integrated circuits have gold bonding wires connecting the die to the legs the most economic way to recover the gold is to use Pyrolysis then use a gold pan to recover the gold wires. Use a magnet to remove anything that sticks, the chip pins are made from Kovar a metal having a very low expansion rate is used in the manufacture of vacuum tubes. @formariz Kovar. Kovar not only has thermal expansion similar to glass, but its nonlinear thermal expansion curve can often be made to match a glass, thus allowing the joint to tolerate a wide temperature range. Chemically, it bonds to glass via the intermediate oxide layer of nickel(II) oxide and cobalt(II) oxide. The proportion of iron oxide is low due to its reduction with cobalt. The bond strength is highly dependent on the oxide layer thickness and character.[4][6] The presence of cobalt makes the oxide layer easier to melt and dissolve in the molten glass. A grey, grey-blue or grey-brown color indicates a good seal. A metallic color indicates lack of oxide, while black color indicates overly oxidized metal, in both cases leading to a weak joint Edited June 7, 2020 by bcgold Share this post Link to post Share on other sites
bc.gold 3,403 #2 Posted June 7, 2020 More scrap yard $$$, catalytic converter liquor. When palladium is the predominant species the liquor is coffee coloured. 1 Share this post Link to post Share on other sites
