Metamorphic, Likely Sedimentary With Quartz Veins

Quartz-rich metamorphic rock, likely quartzite or quartz-veined schist

Quartz (SiO₂) with mica/chlorite-rich schistose matrix; possibly minor feldspar and sulfides

Pyrite-bearing rock, likely quartz vein

Pyrite (FeS₂) in quartz-rich host rock

Clear Quartz

Silicon dioxide (SiO2)

Milky quartz with iron-oxide staining

Quartz (SiO₂), likely ferruginous milky quartz

Iron-stained quartz-rich rock (likely quartzite or quartz vein material)

Quartz (SiO₂), commonly with limonite/goethite iron oxides; possible quartzite matrix

Quartz Vein in Matrix (Breccia / Host Rock with Quartz)

Silicon Dioxide (SiO2) in Host Rock Matrix

Tumbled milky quartz

Quartz (SiO₂), likely milky quartz

Quartz-rich altered rock, possibly quartz vein with mica

Microcrystalline to coarse quartz (SiO₂) with probable muscovite/biotite mica and iron-oxide staining

Quartz-rich rock, possibly iron-stained quartz or quartzite

Quartz (SiO₂), likely with iron-oxide inclusions; exact identification requires testing

Bull Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Chert (with Epidote/Quartz veining)

Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions

Milky quartz-bearing rock (likely quartz vein fragment)

Quartz, silicon dioxide (SiO₂), with probable iron-oxide staining and dark host-rock inclusions

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Iron-rich quartzite or silicified ironstone

Ferruginous quartzite; chiefly microcrystalline quartz (SiO₂) with iron oxides/hydroxides such as hematite and goethite

Galena with Pyrite

Lead Sulfide (PbS) associated with Iron Sulfide (FeS2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Tumbled milky quartz

Quartz (SiO₂), cryptocrystalline to coarse-grained quartz aggregate

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Clear Quartz (Faceted Crystal)

Silicon Dioxide (SiO2)

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Quartz-bearing rock fragment

Likely quartz (SiO₂) with iron-oxide staining and possible host-rock grains

Pyrite-bearing sulfide specimen

Pyrite (FeS₂), possibly mixed with chalcopyrite or other iron sulfides

Tumbled milky quartz

Quartz (SiO₂), cryptocrystalline-to-massive variety

Milky quartz (rough quartz specimen)

Quartz, silicon dioxide (SiO₂)

Polished green aventurine

Quartzite or quartz-rich rock containing fuchsite mica; mainly SiO₂

Milky quartz-bearing rock

Quartz, silicon dioxide (SiO₂), likely massive quartz with iron-oxide staining

Quartz-rich rock, likely milky quartz or quartzite

Quartz (SiO₂), possibly quartzite with iron-oxide staining

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Likely milky quartz

Quartz (silicon dioxide, SiO₂)

Painted River Rock

Artificially Coated Sedimentary Rock

Small polished gemstone chips, likely mixed quartz varieties

Quartz (SiO₂), possibly including smoky quartz and other varieties; exact identification is uncertain from the image

Green apatite crystal

Apatite group; likely fluorapatite, Ca₅(PO₄)₃F

Weathered quartz-rich pebble

Likely milky quartz (SiO₂), possibly a quartz-rich vein fragment

White Buffalo Turquoise (or Howlite/Magnesite)

Calcite/Dolomite or Magnesite with Chert/Quartz inclusions

Weathered quartz-rich rock, possibly quartzite or chalcedony

Quartz (SiO₂), likely in a quartzite or silica-rich matrix

Weathered foliated metamorphic rock, likely schist or gneiss

Mica schist to gneiss; commonly quartz + feldspar + biotite/muscovite

Pyrite-bearing rock, likely pyrite quartzite or sulfide ore

Pyrite (FeS₂), possibly with quartz and minor iron sulfides

Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2)

Milky quartz

Quartz, silicon dioxide (SiO₂)

Milky quartz (massive quartz)

Quartz, silicon dioxide (SiO₂)

Milky quartz (rough crystal fragment)

Quartz, silicon dioxide (SiO₂)