Identify any rockfrom a photo.

Carved limestone architectural fragment

Limestone, predominantly calcite (CaCO₃), possibly weathered fossiliferous or oolitic limestone

Weathered granite

Granite; quartz–feldspar–mica plutonic rock

Granite (likely biotite or hornblende granite)

Coarse-grained felsic intrusive rock; chiefly quartz (SiO₂), plagioclase and potassium feldspar, with minor biotite/hornblende

Tumbled turquoise (probable)

Turquoise — hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O

Likely quartz-rich stone or pale feldspar fragment

Indeterminate; possibly quartz (SiO₂) or feldspar (KAlSi₃O₈–NaAlSi₃O₈)

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Milky quartz (quartz crystal fragment)

Quartz, silicon dioxide (SiO₂)

Calcite crystal (likely Iceland spar)

Calcite, calcium carbonate (CaCO₃)

Quartz-rich gray stone, likely quartzite

Quartzite; predominantly crystalline silicon dioxide (SiO₂)

Selenite (gypsum) wand

Gypsum, CaSO₄·2H₂O; likely satin spar or clear selenite variety

Tumbled brown stone, likely jasper or iron-rich chert

Microcrystalline quartz (SiO₂), possibly hematite/goethite-bearing jasper

Rounded quartz-rich pebble

Massive quartz (silicon dioxide, SiO₂), possibly milky quartz or quartzite