What's That Rock?Quartzite
A hard metamorphic rock formed when sandstone is changed by heat and pressure. It breaks through its grains instead of around them.
How to identify Quartzite
- Very hard: scratches glass
- Breaks with a smooth glassy fracture across grains
- Dense, sugary look
Often confused with
- Sandstonegrains rub off
- Marblesofter
- Vein quartz
Is Quartzite valuable?
Common.
What changes the price
- Common rock: low value as a specimen
- Countertop quartzite slabs are priced by area, color and thickness
- Rare colors and patterns cost more as dimension stone
Uses
- Countertops, aggregate, railway ballast
Care
Safe to wash.
Identifying a stone from a description or a photo is an estimate. Many stones look alike. Ask an expert or a gem lab before you buy, sell or rely on an identification.
Updated October 2026