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Created page with "== Introduction == Quartzite is a hard, non-foliated metamorphic rock which was originally pure quartz sandstone. Sandstone is converted into quartzite through heating and pressure usually related to tectonic compression within orogenic belts. Quartzite is distinguished from sandstone by its fracture. Sandstone fractures along grain boundaries, whereas quartzite is so well indurated (hardened) that it breaks across constituent grains. The interlocking cry..."
