Grain-tin
See TIN.
Granite is a widely known igneous rock, composed of quartz, feldspar, and mica, united in a confused crystallization. Feldspar predominates, and quartz is greater than mica. It is so called because of its granular structure. The decomposition of the feldspar of some kinds of granites produces the kaolin used for porcelain, and for many purposes in metallurgy. When granite decomposes and becomes mixed with organic matter it makes good soil. See KAOLIN; MICA; FELDSPAR; ROCK; EARTHS.