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
Period 5 element electrical contacts and the production of thick-film resistors. A minor application of ruthenium is its use in some platinum alloys. Rhodium is a chemical element that is a rare, silvery-white, hard, and chemically inert transition metal and a member of the platinum group. It has the chemical symbol Rh and atomic number 45. It is composed of only one isotope,Rh. Naturally occurring rhodium is found as the free metal, alloyed with similar metals, and never as a chemical compound. It is one of the rarest precious metals and one of the most costly (gold has since taken over the top