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Phaneritic rock: Anorthosite from the Stillwater Igneous Complex (Neoarchean; Montana) Igneous textures include the rock textures occurring in igneous rocks.Igneous textures are used by geologists in determining the mode of origin of igneous rocks and are used in rock classification.
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In geology, texture or rock microstructure [1] refers to the relationship between the materials of which a rock is composed. [2] The broadest textural classes are crystalline (in which the components are intergrown and interlocking crystals), fragmental (in which there is an accumulation of fragments by some physical process), aphanitic (in which crystals are not visible to the unaided eye ...
The smaller figure before "restoration" The two Knossos snake goddess figurines were found by Evans's excavators in one of a group of stone-lined and lidded cists Evans called the "Temple Repositories", since they contained a variety of objects that were presumably no longer required for use, [5] perhaps after a fire. [6]
Cumulate rocks are named according to their texture; cumulate texture is diagnostic of the conditions of formation of this group of igneous rocks. Cumulates can be deposited on top of other older cumulates of different composition and colour, typically giving the cumulate rock a layered or banded appearance.
This porphyritic texture is indicative of multi-stage cooling of magma. For example, porphyritic andesite will have large phenocrysts of plagioclase in a fine-grained matrix. Also in South Africa , diamonds are often mined from a matrix of weathered clay -like rock ( kimberlite ) called "yellow ground".
"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.
The Bull-Leaping Fresco from Knossos showing bull-leaping, c. 1450 BC; probably, the dark skinned figure is a man and the two light skinned figures are women. The history of Crete goes back to the 7th millennium BC, preceding the ancient Minoan civilization by more than four millennia.