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1158 Journal of Chemical Education October, 1926
57. A nother Preparation.
To
gild silver in a durable fashion. Take some mercury and some leaves of
gold, and make up into the consistency of wax; taking the vessel of
silver, clean it with alum, and taking a little of the waxy material,
lay it on with the polisher and let the material fasten itself on. Do
this five times. Hold the vessel with a genuine linen cloth in order
not to soil it. Then taking some embers, prepare some ashes (and with
them) smooth (it) with the polisher and use as a gold vessel. It can be
submitted to the test for regular gold.
58. Writing in Letters of Gold.
Golden-colored arsenic, 20 drachmas; pulverized glass, 4 staters; of white of egg, 2 staters, white gum, 20 staters, saffron.... after having written, let dry and polish with a tooth.
59. Manufacture of Asem.
Asem
is also prepared with copper; (silver) 2 mina; tin in grains.. 1 mina;
melting first the copper, throw on it the tin and some talc called
chalk, a half to one mina; proceed until you see the silver and the
chalk melt; after which the remainder will have been dissipated and
only the silver will remain, then let it cool, and use it as asem
preferable to the genuine......
The
chemical nature of the mineral or flux called talc or chalk in this
recipe is unknown. Certainly it does not correspond to the substances
of that name that we are acquainted with.
60. Another (Preparation).
Everlasting asem is prepared thus: 1 stater of good asem; add to it 2 staters of refined copper, melt two or three times.
61. Whitening of Tin.
To whiten tin. Having heated (it) with alum and natron, melt.
62. Writing in Letters of Asem.
Dilute some copperas and some sulfur with vinegar; write with the thickened material.
63. Writing in Letters of Gold.
Flower of cnecos, white gum, white of egg mixed
in a shell, and incorporate with bile of tortoise, by estimation as one
does for colors; put into use. The very bitter bile of a calf also
serves for the color.
The plant mentioned here was evidently one containing yellow coloring matter although its exact species is not known.
64. Testing of Asem.
To recognize if asem is false. Place it in brine (and) heat; if it is false, it will blacken.
65. Cleaning of Tin.
Place some gypsum on a rag and scour.
66. Cleaning of Silver. Employ moist alum.
67. Coloring of Asem.
Cinnabar, 1 part, lamellous alum, 1 part, Cimolian earth, 1 part; moisten with sea water and put into use.
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