Silver Britannia

Lesser known standards are coin silver, which is 90% silver, 10% copper, and Mexican silver, which is 95% silver. Britannia silver also is more pure than... 

Britannia silver 95.84% silver, up to 4.16% copper Mexican silver 95% silver, 5% copper... 

Brinell hardness test, 7 bristle feathers, 130, 131 bristles, 126, 148, 161 bristletails, 103 Britannia silver, 28-29, 174 brittleness, 5 brocade, 105 bronze, 29 brooms, 77, 81-82 brown coal, 46 brown ocher, 18 brushes, 76, 77, 81, 82, 148 brushite, 135 bryophyta, bryophytes, 63 bryozoa, 98 Bucerotidae, 143 bucking, 151 buckram, 74... 

In 1986 Britannia Refined Metals (Northfleet, U.K.) introduced technology for the treatment of Parkes cmst, a triple alloy of Ag, Zn, Pb, which by 1992 had been adopted by seven lead refineries (22). The technology consists of a three-stage process in which the silver-rich cmst is first Hquated to reduce its lead content, then placed in a sealed furnace where the 2inc is removed by vacuum distillation and, finally, the silver—lead metal is treated in a bottom blown oxygen cupel (BBOC) to produce a Htharge slag and dorn metal. 

The electro-deposition of cobalt from either of the foregoing solutions on to brass, iron, steel, copper, tin, lead, Britannia metal, and German silver may be effected under conditions similar to those employed for nickel. The deposit is firm, adherent, hard, and uniform. It is readily buffed to a finished surface having a beautiful lustre, possessing a slightly bluish cast, although beautifully white. 

Britannia A process for removing silver from lead, operated by Britannia Refined Metals in England, using ore from the Mount Isa mine in Australia. After initial concentration by the Parkes process and removal of the zinc by vacuum distillation, the mixture, which contains silver (70%), lead, and some copper, is treated in a bottom-blown oxygen cupel lead and copper are removed by the injection of oxygen through a shielded lance. 

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