Quartz or Quartzite?

Quartz is not just a type of rock; it's a mineral, specifically a tectosilicate mineral. Here's a bit more detail:

Composition and Structure
Chemical Formula: SiO₂ (Silicon Dioxide)
Crystal Structure: Quartz has a hexagonal crystal structure, which is why it often forms hexagonal prisms with pyramidal terminations.

Types of Quartz
Quartz appears in various forms, both in nature and in human-made contexts:

Crystalline Quartz: This includes:
Rock Crystal: Clear, transparent quartz.
Amethyst: Purple quartz.
Citrine: Yellow to orange-brown quartz.
Rose Quartz: Pink quartz.
Cryptocrystalline Quartz: This includes:
Chalcedony: A type of quartz with a fibrous structure, often translucent.
Agate: Banded chalcedony with layers of different colors.
Jasper: Opaque, usually red, yellow, or brown, due to impurities.
Onyx: Parallel banded chalcedony, usually black and white.
Macrocrystalline Quartz:
Milky Quartz: White or cloudy due to inclusions.
Smoky Quartz: Brown to gray or black due to irradiation.

Properties
Hardness: Quartz has a Mohs hardness of 7, making it fairly hard and durable.
Luster: Vitreous (glassy) luster when polished.
Cleavage: None, but it has conchoidal fracture, which is characteristic of brittle materials.

Occurrence
Quartz is one of the most common minerals found in the Earth's crust. It forms in igneous, metamorphic, and sedimentary rocks. Its resistance to weathering makes it a major component of sand and many types of soil.

Uses
Industry: Used in the manufacture of glass, ceramics, and as a flux in metal casting.
Electronics: As quartz crystals in watches and other timekeeping devices due to its piezoelectric properties.
Gemstones: Many varieties of quartz are used as gemstones in jewelry.
Construction: As crushed stone or sand in concrete, roads, and building materials.

Cultural Significance
Quartz has been significant in various cultures for its beauty and metaphysical properties, often used in spiritual and healing practices.

In summary, quartz is a mineral with a wide range of varieties and uses, appreciated both for its practical applications and its aesthetic qualities.