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The terms fused quartz and fused silica are used interchangeably but can refer to different manufacturing techniques, resulting in different trace impurities. However fused quartz, being in the glassy state, has quite different physical properties compared to crystalline quartz despite being made of the same substance. [2]
In nature, quartz crystals are often twinned (with twin right-handed and left-handed quartz crystals), distorted, or so intergrown with adjacent crystals of quartz or other minerals as to only show part of this shape, or to lack obvious crystal faces altogether and appear massive. [21] [22]
Frit. A frit is a ceramic composition that has been fused, quenched, and granulated.Frits form an important part of the batches used in compounding enamels and ceramic glazes; the purpose of this pre-fusion is to render any soluble and/or toxic components insoluble by causing them to combine with silica and other added oxides. [1]
Unless stated otherwise, the properties of fused silica (quartz glass) and germania glass are derived from the SciGlass glass database by forming the arithmetic mean of all the experimental values from different authors (in general more than 10 independent sources for quartz glass and T g of germanium oxide glass). The list is not exhaustive.
While quartzite is made almost entirely of mineral quartz, additional minerals can result in different colorings, making some slabs of quartzite lighter or darker or more varied in hue, which ...
Fused quartz is a glass made from chemically pure silica. [68] It has very low thermal expansion and excellent resistance to thermal shock , being able to survive immersion in water while red hot, resists high temperatures (1000–1500 °C) and chemical weathering, and is very hard.
After crystallization the dominant crystal phase in this type of glass-ceramic is a high-quartz solid solution (HQ s.s.). If the glass-ceramic is subjected to a more intense heat treatment, this HQ s.s. transforms into a keatite-solid solution (K s.s., sometimes wrongly named as beta-spodumene). This transition is non-reversible and ...
Fulgurites are formed when lightning strikes the ground, fusing and vitrifying mineral grains. [7] The primary SiO 2 phase in common tube fulgurites is lechatelierite , an amorphous silica glass. Many fulgurites show some evidence of crystallization: in addition to glasses, many are partially protocrystalline or microcrystalline .