igneous
Quartz-rich pegmatite (likely feldspar and quartz)
Granitic pegmatite composed mainly of quartz (SiO₂) and feldspars
AI-generated identification · may be incorrectCoarse, irregular white to cream crystals with tan staining and a glassy-to-dull luster. Quartz is Mohs 7; feldspar is about 6, and both have a crystalline structure, though the small specimen is too irregular to identify cleavage confidently.
Identified More igneous →
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Physical properties
Coarse, irregular white to cream crystals with tan staining and a glassy-to-dull luster. Quartz is Mohs 7; feldspar is about 6, and both have a crystalline structure, though the small specimen is too irregular to identify cleavage confidently.
Formation & geological history
Likely crystallized slowly from silica-rich magma in a pegmatite body, allowing large interlocking crystals to grow. Pegmatites commonly form in the final stages of granitic intrusion, often billions to millions of years ago depending on the region.
Uses & applications
Usually collected as a geological specimen; pegmatite minerals can supply feldspar and quartz for ceramics, glass, and industrial uses.
Geological facts
The image is consistent with a quartz–feldspar-rich rock, but its exact mineral proportions and identity cannot be confirmed visually.
Field identification & locations
Look for interlocking pale crystals, hardness differences, and feldspar cleavage; common in granite regions and pegmatite veins worldwide. A fresh break or simple hardness tests can help distinguish quartz from feldspar.
