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| Formula: | Pb5(PO4)3Cl |  Click to see a larger image |
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| Crystal: | Hexagonal | |||
| Hardness: | 3.5-4 | |||
| Spec. Gr.: | 7.04 | |||
| Streak: | White | |||
| Cleavage: | m(101'0), x(101'1) in traces | |||
| Location: | Les Farges, Correze, France |
| Pyromorphite originates from the weathering of lead sulfide ores. Its name is from the Greek PYROS (fire) and MORPHE (form). The Greek names of these stones enumerated by Erasmus, signify their real or supposed resemblance to certain natural objects. Pyromorphite forms as a secondary mineral in near-surface oxidized ore zones. Easy to see and mine, most good sources are now depleted. High-grade deposits were at Broken Hill, Australia; Roughton Gill mine, Caldbeck Fells, Cumbria, England; Bad Ems, Rheinland-Pfalz, Germany; Bunker Hill mine, Idaho; and the Les Farges mine at Correze, France. Crystallized pyromorphite is quite common, but well-formed, pretty crystals are rare and in heavy demand. It forms in columnar or needle-shaped crystals, and in reniform modules. It easily pseudomorphs after galena and cerussite. Most often it is green, orange, or brown. The Les Farges mine had a short existence (1972-1984), but in a little over a single decade produced many world-class specimens. |
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Bibliography: Bancroft, Peter, Gem and Crystal Treasures, 1984, pg. 365-367. George, Kunz, The Curious Lore of Precious Stones. |
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