Identify any rockfrom a photo.

Iron-stained quartz-rich breccia

Silicified, limonite/goethite-stained breccia; chiefly SiO₂ (quartz) with FeO(OH)·nH₂O iron oxides

Blue faceted gemstone, likely synthetic sapphire or blue glass

Corundum (Al₂O₃) if sapphire; identity cannot be confirmed visually

Milky quartz

Quartz (silicon dioxide, SiO₂)

Quartz-rich metamorphic rock, likely mica schist or gneiss

Quartz–feldspar–mica metamorphic aggregate; exact identification requires thin-section or field tests

Iron-rich metamorphic rock, likely magnetite–hematite-bearing ironstone

Banded or massive iron formation (BIF), chiefly hematite (Fe₂O₃) and magnetite (Fe₃O₄), with quartz and possible iron silicates

Weathered iron-rich volcanic rock (probable basalt/scoria)

Basaltic volcanic rock; mainly plagioclase feldspar, pyroxene, and iron oxides

Pink granite (likely biotite-bearing)

Granitic rock; chiefly quartz, K-feldspar, plagioclase, and biotite

Quartz-rich pegmatitic rock, possibly milky quartz with mica

Pegmatite dominated by quartz (SiO₂), with probable muscovite mica and feldspar

Weathered gray igneous rock, likely granite or granodiorite

Granite–granodiorite; mainly quartz, feldspar, and mica

Porphyritic rhyolite

Rhyolite, a silica-rich volcanic rock; likely quartz–feldspar porphyry

Weathered chert or siliceous limestone

Microcrystalline quartz (SiO₂), possibly with carbonate matrix

Likely black diamond or dark faceted gemstone ring

Uncertain from the photograph; possibly carbon (diamond) or black spinel, set in metal