Schmelze.
(Glass.) A composition of silica, 500; minium, 800; niter, 100; potash, 100. To 500 parts of which add: — 43 parts prismatic borax; 4 parts oxide tin; 4 parts oxide antimony; and a small portion of solution of gold in aqua regia. Heat for 12 hours in a crucible and anneal. The mixture is used for making a ruby glass for flashing colorless articles. See flashing.
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