Mineral In Igneous Rock

Small pale blue-gray rock fragment

Unidentified fine-grained silicate rock; image insufficient for a reliable species-level identification

Porphyritic Granite (or Porphyry)

Porphyritic Igneous Rock

Quartz

SiO2 (Silicon Dioxide)

Basalt

Mafic extrusive igneous rock

Granite Boulder

Felsic Intrusive Igneous Rock

Granite

Felsic intrusive igneous rock

Granite

Phaneritic Felsic Igneous Rock

Granite

Phaneritic intrusive igneous rock

Pink granite pebble

Granite, composed chiefly of quartz, potassium feldspar, and mica

Quartz Pebble

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Granite

Granite (a felsic intrusive igneous rock)

Basalt with Iron Oxidation (Lattice/Veined)

Mafic Volcanic Rock (principally Plagioclase and Pyroxene)

Apatite

Ca5(PO4)3(F,Cl,OH)

Granite

Granite (Felsic Plutonic Rock)

Granite

Granite (Phaneritic Igneous Rock)

Weathered quartz-rich pebble

Milky quartz, SiO₂, possibly quartzite or quartz-veined rock

Small polished or naturally worn stone, possibly quartz-bearing rock

Indeterminate from the blurred image; likely quartz (SiO₂) or a pale feldspar-rich fragment

Foliated Metamorphic Rock (likely Gneiss or Schist)

Gneissic Metamorphic Rock

Epidote-bearing Rock

Epidote / Silicate mineral aggregate

Biotite (Black Mica)

Biotite (K(Mg,Fe++)3AlSi3O10(OH,F)2)

Clear Quartz

Silicon Dioxide (SiO2)

Quartz-veined Basalt or Diabase Pebble

Igneous rock with hydrothermal quartz vein

Gray rock (possibly basalt or fine-grained granite)

Undetermined; no diagnostic minerals are visible

Foliated metamorphic rock, likely gneiss or mica schist

Quartz–feldspar–mica metamorphic rock; exact identification is uncertain from the photograph

Milky quartz vein rock

Quartz (SiO₂), likely in a quartz-rich host rock with minor iron-stained minerals

Basalt with Quartz/Calcite Veins

Extrusive mafic igneous rock with hydrothermal mineralization

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) vein cutting through host rock

Dalmation Stone (Dalmation Jasper)

Peralkaline rock (primarily Feldspar and Quartz with Arfvedsonite spots)

Auriferous Quartz (Gold-bearing Quartz)

Silicon Dioxide (SiO2) with trace Gold (Au) and Iron Oxides

Porphyritic Basalt or Lamprophyre

Extrusive igneous rock with visible phenocrysts

Banded Carnelian Agate

Silicon Dioxide (SiO2)

Quartz with Mica

Silicon Dioxide (SiO2) with Mica group inclusions

Biotite Mica

Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)

Granite

Phaneritic Igneous Rock (Granite)

Basalt

Extrusive Igneous Rock (Mafic)

Granite

Felsic intrusive igneous rock

Purple Dyed Dalmatian Stone

Dyed Peralkaline Trachyte

Granite

Phaneritic Felsic Igneous Rock

Granite

Phaneritic Felsic Igneous Rock

Greenstone

Protolith: Basaltic rock

Fluorite Carving

Fluorite (Calcium Fluoride, CaF2)