igneous

Granite

Phaneritic felsic intrusive igneous rock; mainly quartz, alkali feldspar, plagioclase, and biotite/hornblende

AI-generated identification · may be incorrect

Coarse, interlocking grains with pink-tan feldspar, gray-white quartz, and black mica; vitreous quartz and feldspar luster, no layering, typically Mohs 6–7, specific gravity about 2.63–2.75.

Identified August 17, 2026More igneous →

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At a glance

Common name: Granite
Scientific name: Phaneritic felsic intrusive igneous rock; mainly quartz, alkali feldspar, plagioclase, and biotite/hornblende
Category: igneous
Identified: August 17, 2026
Method: Standard

AI Estimated Value

Common rough or construction-grade pieces: $5–$30; attractive polished slabs or collector specimens: roughly $50–$300+, depending on size, pattern, and provenance.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Coarse, interlocking grains with pink-tan feldspar, gray-white quartz, and black mica; vitreous quartz and feldspar luster, no layering, typically Mohs 6–7, specific gravity about 2.63–2.75.

Formation & geological history

Forms when silica-rich magma slowly crystallizes deep in the continental crust, commonly during Precambrian to Phanerozoic mountain-building events; the image may show weathering or surface staining.

Uses & applications

Widely used for countertops, monuments, building stone, paving, crushed aggregate, and architectural cladding; polished slabs have commercial rather than gemstone value.

Geological facts

Its visible crystals reflect slow underground cooling. Granite is distinguished from similar rocks by abundant quartz and feldspar plus its coarse, speckled texture.

Field identification & locations

Common worldwide, especially in continental shields and mountain belts; identify it by testing for quartz, observing interlocking crystals, and checking that it lacks foliation. Exact locality requires a fresh surface or laboratory analysis.