Metamorphic Rock

Quartzite

The Indestructible Sandstone

White
Pink
Gray
Pale Green

Quick Facts

FormulaSiOβ‚‚ (recrystallized quartz grains)
SystemNone (polycrystalline rock)
LusterVitreous to Greasy
StreakWhite
TransparencyOpaque to Translucent
Sp. Gravity2.65
Mohs Hardness
7

Formation & Origin

Quartzite forms when sandstone is metamorphosed by heat and pressure. The original sand grains (which were individual quartz crystals) recrystallize and fuse together, creating an interlocking mosaic of quartz that is far harder and more durable than the original sandstone.

The transformation is dramatic. Sandstone breaks around its grains (you can see individual sand grains on broken surfaces). Quartzite breaks through its grains, producing a smooth, conchoidal fracture because the grain boundaries have been obliterated by recrystallization.

Pure quartzite is white. Pink quartzite (like South Dakota's Sioux Quartzite) contains iron oxide. Green quartzite may contain fuchsite mica. Quartzite is one of the most durable natural materials available, resisting weathering, heat, and chemicals. It's increasingly popular as a countertop material, marketed as a premium alternative to granite.

Identification Guide

Quartzite is identified by its extreme hardness (Mohs 7, scratches steel and glass), granular texture of fused quartz grains, conchoidal fracture (breaks through grains, not around them), and lack of acid reaction.

Distinguish from marble (softer, effervesces in acid), sandstone (softer, breaks around grains, gritty feel), and granite (contains visible feldspar and mica in addition to quartz).

Spotting Fakes

In the countertop industry, some 'quartzite' is actually dolomite marble or other softer stone that won't hold up as well. True quartzite should scratch glass easily and not react with acid. The term 'soft quartzite' is sometimes used for dolomite marble, which is misleading. If you can scratch it with a knife, it's not quartzite.

Cultural & Metaphysical Traditions

Presented as cultural traditions, not scientific evidence

Quartzite is associated with endurance, determination, and the transformation of something ordinary into something extraordinary. The metamorphic journey from loose sand to fused stone mirrors themes of personal growth through pressure. Practitioners use it for persistence and long-term goal setting.

Where It's Found

Worldwide - Wherever sandstone has been metamorphosed

Very common globally

Brazil - Various

Decorative quartzite slabs

India - Rajasthan

Commercial quarrying

United States - South Dakota (Sioux Quartzite)

Famous pink quartzite, 1.7 billion years old

Price Guide

Entry$2-10 specimens
Mid-Range$50-150/sq ft countertop slabs
Collector$15-60 polished display specimens

Good to Know

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Scratch test: At hardness 7, Quartzite can scratch glass and steel. It's durable enough for any type of jewelry.

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Sources: Found in 4 notable locations worldwide, from Worldwide to United States.

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Heft test: Quartzite has average mineral density (2.65). It feels about as heavy as you'd expect from a stone its size.