Definition

Noun: 1. A hard, dense, metamorphic rock: Quartzite is a type of rock formed when sandstone, which is rich in quartz, is subjected to intense heat and pressure (metamorphism). This process causes the original quartz grains to recrystallize and fuse together into a solid, interlocking mass of quartz crystals.

Usage

Quartzite is used as a singular, uncountable noun when referring to the rock as a material. It can be used as a countable noun when referring to specific types or instances of this rock.

Examples

• General Material:

  • The countertop is made of polished quartzite, which is both beautiful and durable.
  • Quartzite is often used in construction because of its hardness and resistance to weathering.

• Specific Instance/Type:

  • The mountain range is composed primarily of ancient quartzites.
  • This particular quartzite has a distinctive pink hue.

Advanced Usage

• Geological Context: In geology, "quartzite" specifically refers to a metamorphic rock. A very similar-looking rock called "orthoquartzite" is a sedimentary sandstone that has been cemented by silica, but not fully recrystallized by metamorphism. In informal contexts, both may be called quartzite.
  • True metamorphic quartzite will fracture across the original quartz grains, not around them.

Variants and Related Words

• Quartz (noun): The mineral, composed of silicon dioxide (SiO₂), which is the primary component of quartzite.
• Sandstone (noun): The sedimentary rock precursor to quartzite.
• Metamorphic (adjective): Describing rocks changed by heat and pressure, like quartzite.
• Orthoquartzite (noun): A highly cemented, non-metamorphosed sandstone that resembles true quartzite.

Synonyms

• Metamorphosed sandstone (descriptive synonym)
• Silica rock (general, less precise)

Related Phrases/Compounds

• Quartzite formation: A geological stratum or body composed of quartzite.
  • The quartzite formation creates a prominent ridge in the landscape.
• Quartzite quarry: A site where quartzite is extracted.
  • The stone for the building was sourced from a local quartzite quarry.

Noun

1. hard metamorphic rock consisting essentially of interlocking quartz crystals