Emission spectroscopy
Spectroscopy also provides a precise analytical method for finding the constituents in material having unknown chemical composition. In a typical spectroscopic analysis, a concentration of a few parts per million of a trace element in a material…
Matte
Matte, crude mixture of molten sulfides formed as an intermediate product of the smelting of sulfide ores of metals, especially copper, nickel, and lead. Instead of being smelted directly to metal, copper ores are usually smelted to…
Smelting
Smelting, process by which a metal is obtained, either as the element or as a simple compound, from its ore by heating beyond the melting point, ordinarily in the presence of oxidizing agents, such as air,…
Stone Age
Stone Age, prehistoric cultural stage, or level of human development characterized by the creation and use of stone tools. The Stone Age, whose origin coincides with the discovery of the oldest known stone tools,…
Silver
Silver (Ag), chemical element, a white lustrous metal valued for its decorative beauty and electrical conductivity. Silver is located in Group 11 (Ib) and Period 5 of the periodic table, between copper (Period 4) and gold (Period 6), and…
Gold
Gold (Au), chemical element, a dense lustrous yellow precious metal of Group 11 (Ib), Period 6, of the periodic table. Gold has several qualities that have made it exceptionally valuable throughout history. It is attractive…
Metallurgy
Metallurgy, art and science of extracting metals from their ores and modifying the metals for use. Metallurgy customarily refers to commercial as opposed to laboratory methods. It also concerns the chemical, physical,…
Mineral deposit
Mineral deposit, aggregate of a mineral in an unusually high concentration. About half of the known chemical elements possess some metallic properties. The term metal, however, is reserved for those chemical elements that possess two or more of the…
Gangue
Smelting Perhaps 1,000 years after humans learned about melting virgin copper, they found that still another stone, a brittle one directly useless for tools, would produce liquid copper if sufficiently heated…
