igneous
Pegmatitic quartz–feldspar rock
Granitic pegmatite, composed mainly of quartz (SiO₂) and feldspar; mica may also be present
AI-generated identification · may be incorrectCoarse, irregular interlocking crystals; mostly white to pale cream with glassy or pearly reflections and minor dark inclusions. Quartz hardness 7; feldspar about 6; the rock has no single crystal structure or hardness.
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Physical properties
Coarse, irregular interlocking crystals; mostly white to pale cream with glassy or pearly reflections and minor dark inclusions. Quartz hardness 7; feldspar about 6; the rock has no single crystal structure or hardness.
Formation & geological history
Likely formed as slowly cooled, water-rich magma crystallized in a shallow igneous intrusion; pegmatites commonly formed during late stages of granitic activity, often in Precambrian terranes.
Uses & applications
Ordinary pieces are mainly collected as geological specimens; pegmatites can also supply feldspar, quartz, mica, and, in some deposits, gemstones or lithium-bearing minerals.
Geological facts
The large, pale reflective grains are consistent with quartz and feldspar, but a photograph cannot confirm the mineral proportions or exclude other pale minerals.
Field identification & locations
The reported location in northeastern Somalia is compatible with crystalline basement rocks and pegmatites, though this specific specimen cannot be matched to a locality from the image alone. Check for glassy, hard quartz grains and feldspar grains that may show flat cleavage surfaces.
