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"Imperial Porphyry" from the Red Sea Mountains of Egypt A waterworn cobble of porphyry Rhyolite porphyry from Colorado; scale bar in lower left is 1 cm (0.39 in). Porphyry (/ ˈ p ɔːr f ə r i / POR-fə-ree) is any of various granites or igneous rocks with coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass.
Porphyry (geology), an igneous rock with large crystals in a fine-grained matrix, often purple, and prestigious Roman sculpture material; Shoksha porphyry, quartzite of purple color resembling true porphyry mined near the village of Shoksha, Karelia, Russia; Porphyritic, the general igneous texture of a rock with two distinct crystal ...
(pl.) aboiteaux A sluice or conduit built beneath a coastal dike, with a hinged gate or a one-way valve that closes during high tide, preventing salt water from flowing into the sluice and flooding the land behind the dike, but remains open during low tide, allowing fresh water precipitation and irrigation runoff to drain from the land into the sea; or a method of land reclamation which relies ...
Porphyry deposits account for most of the copper and molybdenum world production, 60 and 95 percent of its supply respectively. [1] Porphyry-type ore deposits form in hydrothermal fluid circulation systems developed above and around high-level, subvolcanic felsic to intermediate magma chambers and/or cooling plutons. The ore is temporally and ...
The Isagoge (Greek: Εἰσαγωγή, Eisagōgḗ; / ˈ aɪ s ə ɡ oʊ dʒ iː /) or "Introduction" to Aristotle's "Categories", written by Porphyry in Greek and translated into Latin by Boethius, was the standard textbook on logic for at least a millennium after his death.
The term pulse is used for the seeds of plants from the Fabaceae family (legumes), such as beans, pea, lentil and chickpea. Pulses supply proteins and form chief source in vegetarian food. Leguminous plants fix nitrogen in root nodules - produced with the help of nitrogen fixing bacteria.
A key event in the conservation of plant genetic resources was the establishment of the International Board for Plant Genetic Resources (IBPGR) (now Bioversity International) in 1974, whose mandate was to promote and assist in the worldwide effort to collect and conserve the plant germplasm needed for future research and production. IBPGR ...
Andesite porphyry from summit of O'Leary Peak. This is an extrusive porphyritic rock, as the pink (and black) phenocrysts are clearly visible, in contrast to the grey groundmass with its microscopic crystals.