Ads
related to: what is porphyry glass tile
Search results
Results From The WOW.Com Content Network
Glass was used in mosaics as early as 2500 BC, but it was not until the 3rd century BC that innovative artisans in Greece, Persia, and India created glass tiles.. Whereas clay tile is dated as early as 8,000 BC, there were significant barriers to the development of glass tile, including the high temperatures required to melt glass and the complexities of annealing glass curves.
"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 result is a natural amorphous glass with few or no crystals. Examples include obsidian. Pegmatitic texture occurs during magma cooling when some minerals may grow so large that they become massive (the size ranges from a few centimetres to several metres). This is typical of pegmatites.
Purpurin (Italian: Porporino; Latin: Haematinum, derived from Greek haimátinos = "of blood"; German: Hämatinon), sometimes referred to as glass porphyr, is an opaque glass of brownish to lustrous deep-reddish color which in classical antiquity was used for residential luxury objects, mosaics and various decorative purposes.
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 ...
Rhyolites that cool too quickly to grow crystals form a natural glass or vitrophyre, also called obsidian. [13] Slower cooling forms microscopic crystals in the lava and results in textures such as flow foliations, spherulitic, nodular, and lithophysal structures. Some rhyolite is highly vesicular pumice. [5]