igneous
Quartz-rich pegmatite (likely quartz with feldspar and mica)
Granite/pegmatite; chiefly SiO₂ quartz, with feldspar and possible mica or chlorite
AI-generated identification · may be incorrectCoarse, irregular crystalline texture; translucent white to gray quartz, white feldspar, and greenish mica/minerals. Quartz hardness 7, feldspar 6–6.5, mica 2–3; vitreous to pearly luster, poor cleavage overall, and typical specific gravity around 2.6–2.7.
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Physical properties
Coarse, irregular crystalline texture; translucent white to gray quartz, white feldspar, and greenish mica/minerals. Quartz hardness 7, feldspar 6–6.5, mica 2–3; vitreous to pearly luster, poor cleavage overall, and typical specific gravity around 2.6–2.7.
Formation & geological history
Likely formed when silica-rich magma cooled slowly in a shallow intrusive vein, allowing large crystals to grow; pegmatites commonly formed during late stages of Precambrian to younger granitic intrusions.
Uses & applications
Used as a source of quartz, feldspar, mica, and rare metals; attractive pieces are collected, while similar material may be used for countertops, aggregate, and ceramics.
Geological facts
The specimen appears to contain abundant milky quartz and a greenish inclusion, possibly mica, chlorite, epidote, or tourmaline; exact identification requires a fresh surface, hardness testing, and ideally a microscope or chemical analysis.
Field identification & locations
Common in granite terrains and pegmatite veins worldwide. Look for interlocking large crystals, quartz that scratches glass, feldspar cleavage, and flaky mica; it is not visibly a single gemstone.
