igneous
Polished/tumbled quartz-rich pegmatite
Quartz–feldspar pegmatite, with iron-oxide staining; chiefly SiO₂ and KAlSi₃O₈–NaAlSi₃O₈
AI-generated identification · may be incorrectCoarse-grained, translucent white to honey-orange and pink, with vitreous to waxy luster; quartz hardness ~7 and feldspar ~6–6.5, no obvious cleavage in quartz but feldspar cleavage may show. The rounded surface appears polished or naturally water-worn.
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Physical properties
Coarse-grained, translucent white to honey-orange and pink, with vitreous to waxy luster; quartz hardness ~7 and feldspar ~6–6.5, no obvious cleavage in quartz but feldspar cleavage may show. The rounded surface appears polished or naturally water-worn.
Formation & geological history
Likely formed as a late-stage, silica-rich intrusive melt that cooled slowly in a granite-associated pegmatite vein, producing large quartz and feldspar crystals; age depends on locality, commonly Precambrian to Mesozoic. Orange-red areas are probably hematite or limonite staining.
Uses & applications
Used as a decorative stone, lapidary material, specimen, and occasionally aggregate; attractive pieces may be cut into cabochons or polished slabs.
Geological facts
The pink and cream zones are typically feldspar, while translucent gray or honey areas are quartz. Iron oxides can create vivid red-orange coloration without being a separate gemstone.
Field identification & locations
Identify by its very coarse interlocking crystals, glassy quartz, blocky feldspar, and lack of bubbles or uniform glassy texture; common in granitic terrains worldwide, including Brazil, Madagascar, India, and the United States.
