Hierarchy classification:

1. top of the aat hierarchies
2. Materials Facet
3. Materials (hierarchy name)
4. materials (substances)
5. [materials by composition]
6. inorganic material
7. mineral
8. quartz (mineral)

Anotations

Scope note:

A transparent variety of the silica mineral quartz that is valued for its clarity and total lack of color or flaws. Vessels and spheres have been carved from large crystals since ancient times, and the application of the word "crystal" to fine glassware derives from this practice. Quartz crystal formerly was used extensively as a gemstone, usually brilliant-cut, although it has now been largely replaced by glass; rhinestones originally were quartz pebbles found in the Rhine River. The optical properties of quartz crystal led to its use in lenses and prisms; its piezoelectric properties are used to control the oscillation of electrical circuits. Its physical properties are those of quartz.