Pegmatite
A pegmatite is an igneous rock with a very rough texture, which has large interlocking crystals[1] that are usually bigger than Lua error in Module:Convert at line 1850: attempt to index local 'en_value' (a nil value). and sometimes bigger than Lua error in Module:Convert at line 1850: attempt to index local 'en_value' (a nil value)..[2]
Many of the world's largest crystals are found in pegmatites. These include crystals of quartz, mica, beryl, and tourmaline. Some of these crystals are over 10 m (33 ft) long.[3]
Etymology
The word pegmatite comes from the Homeric Greek word, πήγνυμι (pēgnymi), which means “to bind together." This refers to the interlocked crystals in the rock's texture.[4]
Pegmatite Media
Pegmatite containing lepidolite, tourmaline, and quartz from the White Elephant Mine in the Black Hills, South Dakota
Proterozoic pegmatite swarm in the headwall of the cirque of a small mountain glacier, northeastern Baffin Island, Nunavut
Pegmatitic granite with pink potassium feldspar crystals, surrounding a finer-grained cumulate-filled enclave, Rock Creek Canyon, eastern Sierra Nevada, California
Elbaite tourmaline (olive-green) and lepidolite mica (violet), from a lithium-enriched pegmatite in Brazil
Pegmatite (light colored) in dark mica schist, Île de Noirmoutier, France
Pegmatite (pink), Isle of Skye, Scotland
References
- ↑ Jackson, Julia A., ed. (1997). "Pegmatite". Glossary of Geology (4th ed.). Alexandria, Viriginia: American Geological Institute. ISBN 0922152349.
- ↑ Blatt, Harvey; Tracy, Robert J. (1996). Petrology: Igneous, Sedimentary, and Metamorphic (2nd ed.). New York: W.H. Freeman. p. 73. ISBN 0716724383.
- ↑ Schwartz, G. (1928). "The Black Hills Mineral Region". American Mineralogist. 13: 56–63.
- ↑ London, David; Morgan, George B. (2012-08-01). "The Pegmatite Puzzle". Elements. 8 (4): 263–68. doi:10.2113/gselements.8.4.263. ISSN 1811-5209.