The Sincerely Discovered Art of Assaying and Refining of the Venetians

26.

To test gold.

If you wish to test gold, set the cupels also as thought of before with the silver, and while they are getting hot, cut the test sample. Then take 1 mark, that is 12 carats, and cut the gold according to it. Afterwards take a 36 Referring to a specific coin or weight standard, the "Schreckenberger"., that is, a Schreckenberger that is very clean, and cut from it twenty-three carats' weight, and put the gold and silver from the Schreckenberger together in a small paper. And when the cupels are hot, first set in one lot of lead, and when it has melted, set the gold with the trim into the lead, and let it go off together. And when it has gone off, let it cool down very gently so that the grain does not jump. Always make 2 tests together, so you can see if they are equal or not. Then take those 2 grains and hammer them very thin; one must glow them often before they are hammered thin, and hammer them lengthwise. But if it is not malleable, one dare not hammer it so thin. And when it is hammered thin, turn it into a coil and put it into a good small glass flask, and into it 2 lots of Scheide-Wasser parting acid/nitric acid. Set the flask with the test sample on a small tripod over a gentle ember, so that it becomes hot very gently. It will first become entirely brown, then it becomes white again. And when it becomes white, and the large flowers Crystals or bubbles formed during reaction. rise up on the water, then it has enough. Take it down, and put