Calamine (mineral) enough was known of metallic zinc to make brass solder directly by combining copper and spelter (zinc ingots). In 1738 a patent was granted to William Champion, a Bristol brass founder, for the large-scale reduction of calamine to produce spelter. In 1684 a paper presented to the Royal Society touched on the medicinal and veterinary properties of the compound when in finely powdered form. Calamine (mineral) Calamine is a historic name for an ore of zinc. The name "calamine" was derived from "lapis calaminaris", a Latin corruption of Greek "cadmia (καδμία)", the old name for zinc ores in general. The
Brass over lead content. In laboratory tests, state researchers found the average brass key, new or old, exceeded the California Proposition 65 limits by an average factor of 19, assuming handling twice a day. In April 2001 manufacturers agreed to reduce lead content to 1.5%, or face a requirement to warn consumers about lead content. Keys plated with other metals are not affected by the settlement, and may continue to use brass alloys with higher percentage of lead content. Also in California, lead-free materials must be used for "each component that comes into contact with the wetted surface of pipes and