The early literature provides many methods for preparing
the pigment, most of which seem relatively
cumbersome. (See Appendix D, below.) Here is a rapid and
straightforward synthesis that produces enough pigment
to provide 0.05% Au in a 100-gram test batch of
glaze. Doubling the amount of gold chloride provides
0.1% Au, and produces deeper color in the fired glaze.
“Step 0”: Before you start, it is helpful to
dissolve 1 gram of AuCl3 in 12 grams of
distilled water. 1 gram of the resulting solution
contains approximately 50 milligrams of gold, which is
required in Step 2 of the preparation.
Step 1: Suspend 5 grams of Al(OH)3 (Aluminum
Hydroxide, often inaccurately referred to as
“Alumina Hydrate”) in approximately 12 grams
of distilled water (the amount is not crucial) at room
temperature, with stirring. Other substrates may be used
in place of Al(OH)3, but see Note 2, below.
Step 2: Continue stirring the resulting suspension, and
add 50 mg of gold » Read the rest