| pyrolusite | <chemical> Manganese dioxide, a mineral of an iron-black or dark steel-gray colour and metallic luster, usually soft. Pyrolusite parts with its oxygen at a red heat, and is extensively used in discharging the brown and green tints of glass (whence its name). Origin: Pyro- + Gr. To loose, or a loosing. Source: Websters Dictionary (01 Mar 1998) |
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| pitch-ore | <chemical> Pitchblende. Source: Websters Dictionary (01 Mar 1998) |
| ore | 1. The native form of a metal, whether free and uncombined, as gold, copper, etc, or combined, as iron, lead, etc. Usually the ores contain the metals combined with oxygen, sulphur, arsenic, etc. (called mineralizers). 2. <chemical> A native metal or its compound with the rock in which it occurs, after it has been picked over to throw out what is worthless. 3. Metal; as, the liquid ore. Ore hearth, a low furnace in which rich lead ore is reduced; also called Scotch hearth. Origin: AS. Ra; cf. Ar brass, bronze, akin to OHG. R, G. Ehern brazen, Icel. Eir brass, Goth. Ais, L. Aes, Skr. Ayas iron. 210. Cf. Ora, Era. Source: Websters Dictionary (01 Mar 1998) |