“quartz”的概念、定义、翻译、参考文献-科学参考

quartz

Physics

The most abundant and common mineral, consisting of crystalline silica (silicon dioxide, SiO₂), crystallizing in the trigonal system. It has a hardness of 7 on the Mohs’ scale. The mineral has the property of being piezoelectric and hence is used to make oscillators for clocks (see quartz clock), radios, and radar instruments. It is also used in optical instruments and in glass, glaze, and abrasives.

Chemistry

The most abundant and common mineral, consisting of crystalline silica (silicon dioxide, SiO₂), crystallizing in the trigonal system. It has a hardness of 7 on the Mohs scale. Well-formed crystals of quartz are six-sided prisms terminating in six-sided pyramids. Quartz is ordinarily colourless and transparent, in which form it is known as rock crystal. Coloured varieties, a number of which are used as gemstones, include amethyst, citrine quartz (yellow), rose quartz (pink), milk quartz (white), smoky quartz (grey-brown), chalcedony, agate, and jasper. Quartz occurs in many rocks, especially igneous rocks such as granite and quartzite (of which it is the chief constituent), metamorphic rocks such as gneisses and schists, and sedimentary rocks such as sandstone and limestone. The mineral is piezoelectric and is used in oscillators. It is also used in optical instruments and in glass, glaze, and abrasives.

Electronics and Electrical Engineering

Naturally occurring crystalline silicon dioxide (SiO₂). It exhibits marked piezoelectric properties and is frequently used as the piezoelectric crystal in piezoelectric oscillators. It also exhibits marked dielectric strength.
Quartz may be readily drawn into extremely fine uniform filaments that are very strong, elastic, and physically and chemically stable. Such quartz fibres are frequently used as torsion threads in delicate measuring instruments, such as electrometers.

Geology and Earth Sciences

Widely distributed rock‐forming silicate mineral SiO₂ with the related semi‐precious varieties rose quartz (pink), amethyst (purple), cairngorm (dark brown and similar to smoky quartz, although the original cairngorms from the Scottish mountain range were of topaz), citrine (light brown); sp. gr. 2.65; hardness 7; trigonal; commonly colourless or white, but can occur in a variety of colours; vitreous lustre; crystals usually six‐sided prisms terminated by six‐faced pyramids, the prisms often striated, also occurs extensively in massive form; no cleavage; conchoidal fracture; found in many igneous and metamorphic rocks, extensively in clastic rocks, and a common gangue mineral in mineral veins. See also agate; chalcedony; coesite; cristobalite; flint; jasper; onyx; opal; stishovite; tridymite.

单词	quartz
释义	quartz Physics The most abundant and common mineral, consisting of crystalline silica (silicon dioxide, SiO₂), crystallizing in the trigonal system. It has a hardness of 7 on the Mohs’ scale. The mineral has the property of being piezoelectric and hence is used to make oscillators for clocks (see quartz clock), radios, and radar instruments. It is also used in optical instruments and in glass, glaze, and abrasives. Chemistry The most abundant and common mineral, consisting of crystalline silica (silicon dioxide, SiO₂), crystallizing in the trigonal system. It has a hardness of 7 on the Mohs scale. Well-formed crystals of quartz are six-sided prisms terminating in six-sided pyramids. Quartz is ordinarily colourless and transparent, in which form it is known as rock crystal. Coloured varieties, a number of which are used as gemstones, include amethyst, citrine quartz (yellow), rose quartz (pink), milk quartz (white), smoky quartz (grey-brown), chalcedony, agate, and jasper. Quartz occurs in many rocks, especially igneous rocks such as granite and quartzite (of which it is the chief constituent), metamorphic rocks such as gneisses and schists, and sedimentary rocks such as sandstone and limestone. The mineral is piezoelectric and is used in oscillators. It is also used in optical instruments and in glass, glaze, and abrasives. Electronics and Electrical Engineering Naturally occurring crystalline silicon dioxide (SiO₂). It exhibits marked piezoelectric properties and is frequently used as the piezoelectric crystal in piezoelectric oscillators. It also exhibits marked dielectric strength. Quartz may be readily drawn into extremely fine uniform filaments that are very strong, elastic, and physically and chemically stable. Such quartz fibres are frequently used as torsion threads in delicate measuring instruments, such as electrometers. Geology and Earth Sciences Widely distributed rock‐forming silicate mineral SiO₂ with the related semi‐precious varieties rose quartz (pink), amethyst (purple), cairngorm (dark brown and similar to smoky quartz, although the original cairngorms from the Scottish mountain range were of topaz), citrine (light brown); sp. gr. 2.65; hardness 7; trigonal; commonly colourless or white, but can occur in a variety of colours; vitreous lustre; crystals usually six‐sided prisms terminated by six‐faced pyramids, the prisms often striated, also occurs extensively in massive form; no cleavage; conchoidal fracture; found in many igneous and metamorphic rocks, extensively in clastic rocks, and a common gangue mineral in mineral veins. See also agate; chalcedony; coesite; cristobalite; flint; jasper; onyx; opal; stishovite; tridymite.
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