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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 ...
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 ...
It can be defined as "the variety and variability of animals, plants and micro-organisms at the genetic, species and ecosystem levels that sustain the ecosystem structures, functions and processes in and around production systems, and that provide food and non-food agricultural products.” [1] It is managed by farmers, pastoralists, fishers ...
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.
Mons Porphyrites (today Jabal Abu Dukhkhan) is the mountainous site of a group of ancient quarries in the Red Sea Hills of the Eastern Desert in Egypt.Under the Roman Empire, they were the only known source of the purple "imperial" variety of porphyry.
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.
Plants that originated in the tropics, like tomato or maize, don't go through cold hardening and are unable to survive freezing temperatures. [3] The plant starts the adaptation by exposure to cold yet still not freezing temperatures. The process can be divided into three steps.