igneous
Weathered feldspar-rich granite or pegmatite
Coarse-grained granitoid, chiefly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), and plagioclase, with minor mica/iron oxides
AI-generated identification · may be incorrectCream-white, coarse crystalline texture with earthy brown weathering; likely vitreous-to-pearly luster and feldspar cleavage. Estimated hardness is about 6–7 Mohs, with irregular fracture and typical specific gravity near 2.6–2.7.
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Physical properties
Cream-white, coarse crystalline texture with earthy brown weathering; likely vitreous-to-pearly luster and feldspar cleavage. Estimated hardness is about 6–7 Mohs, with irregular fracture and typical specific gravity near 2.6–2.7.
Formation & geological history
Formed by slow cooling of silica-rich magma underground, allowing large crystals to grow; its exact geological age cannot be determined from the image and may range from Precambrian to younger. Brown coloration reflects surface oxidation and weathering.
Uses & applications
Commonly used as crushed stone, aggregate, building stone, countertops, and monuments; attractive coarse pieces may be collected as mineral specimens.
Geological facts
The prominent pale crystals and granular texture distinguish it from limestone or concrete, though the image is not sufficient for a definitive identification. A glassy quartz grain would scratch glass, while feldspar generally would not.
Field identification & locations
Common worldwide, especially in continental mountain belts and granitic batholiths. Check for interlocking crystals, quartz’s glassy appearance, and feldspar cleavage; a hardness or acid test can refine identification.
