Sedimentary Rock (Possibly Conglomerate Or Breccia With A Quartz Vein)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (likely a form of massive or vein quartz)

Quartz (SiO₂)

Banded gneiss (likely biotite-rich gneiss)

Gneiss; chiefly quartz, feldspar, biotite, and possibly hornblende

Weathered limestone

Calcite-rich limestone (CaCO₃), possibly fossiliferous or dolomitic

Wishing Stone (Sandstone with Quartz Vein)

Arenite with Quartzite intrusion (SiO₂)

Quartz-veined Limestone

Sedimentary limestone with hydrothermal quartz/calcite veins (CaCO3 / SiO2)

Quartz Vein Rock

Silicon dioxide (SiO2) within a host rock matrix

Quartz (Bull Quartz)

Silicon Dioxide (SiO2)

Milky Quartz on Matrix

Silicon Dioxide (SiO2)

Agate (Puddingstone style)

Silicon Dioxide (SiO2) with impurities

Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Quartz with Sericite and Cinnabar

Silicon Dioxide (SiO2) with muscovite/sericite and mercury sulfide (HgS)

Rock Crystal Quartz

Quartz (SiO₂)

Rounded gray river pebble, likely fine-grained sandstone or siltstone

Indeterminate clastic sedimentary rock; possibly quartz-rich sandstone or siltstone

Quartz Vein Rock

Silicon Dioxide (SiO2)

Quartz Vein in Basalt

Silica-infilled basaltic host rock

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert Pebble with Quartz Veining

Microcrystalline Quartz (SiO2)

River Cobble (likely Metasedimentary or Basalt)

Metamorphosed Siltstone or Altered Fine-grained Igneous Rock

Copper-bearing Quartz Vein in Host Rock

Quartz with Malachite/Chrysocolla staining

Quartz in Matrix (or Quartz Vein Rock)

Silicon Dioxide (SiO2) with host rock

Jasper

Jasper (Cryptocrystalline variety of Quartz, SiO2)

Quartz (variety of colors)

SiO2 (Silicon Dioxide)

Small rounded quartz pebble

Quartz (SiO₂), likely milky or iron-stained quartz

Gabbro or Diorite with Quartz/Epidote Vein

Intrusive Igneous Rock (Plutonic)

Quartz Vein in Host Rock

Quartz (SiO2) in metamorphic host rock (likely schist or phyllite)

Quartz Vein in Granite Pebble

Granitic rock with Quartz (SiO2) vein intrusion

Gold-bearing Quartz Vein in Mafic Rock

Hydrothermal Quartz Vein within Greenschist/Amphibolite facies (SiO2 with Au)

Red jasper-like chalcedony pebble

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper

Likely weathered quartz-rich rock, possibly smoky quartz or chert

Quartz (SiO₂), though exact identification is uncertain from the photograph

Quartz Geode or Vein Quartz

Silicon Dioxide (SiO2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) in matrix

Asphalt Concrete

Bituminous Concrete (Anthropic Rock)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Quartz-veined metamorphic rock, likely greenschist or altered basalt

Chlorite–actinolite schist or metabasalt with a milky quartz vein

Quartzite

Metamorphic Rock (Mainly SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz Vein in Gneiss or Schist

Metamorphic rock with SiO2 vein

Chert (with Quartz vein)

Chert (Silicon Dioxide, SiO2)

Likely weathered gray stone or chert fragment

Uncertain; possibly microcrystalline quartz (SiO₂)-rich chert