Metamorphic (Likely Gneiss Or Schist Based On Texture)

Banded Quartz with Host Rock / Quartz Vein Pebble

Silicon Dioxide (SiO2) in Metamorphic Matrix

Ruby

Corundum (Al2O3:Cr)

Slate

Foliated Metamorphic Rock (primarily composed of Muscovite, Chlorite, and Quartz)

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Sandstone

Arenite (primarily SiO2 with trace Fe2O3)

Blue Quartzite (likely dyed)

Silicon dioxide (SiO2) with likely color treatment

Migmatite

Migmatite (Mixed metamorphic-igneous rock)

Sandstone (Arkose)

Arkose Sandstone (principally SiO2 with Feldspar)

Quartzite

Quartzite (primarily SiO2)

Quartzite (specifically an iron-stained or Carnelian-colored variety)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chalk (Sedimentary Limestone)

Calcite (CaCO3)

Basalt with Plagioclase Porphyry

Porphyritic Basalt

Likely basalt fragment

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene with possible olivine

Weathered quartz-rich river cobble, possibly quartzite

Quartzite (mostly microcrystalline SiO₂), tentatively identified

Rounded iron-stained quartzite or sandstone pebble

Quartzite, predominantly SiO₂, with iron-oxide staining

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Jade (likely nephrite)

Nephrite jade: interlocking actinolite–tremolite amphibole, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂; exact identification requires testing

Rounded river pebble, likely quartz-rich sandstone or quartzite

Indeterminate quartz-rich clast; predominantly SiO₂

N/A - Image does not contain a rock or mineral

Anthropogenic textile material

Diorite (Gneissic)

Diorite with possible metamorphic foliation

Blue Sapphire (Raw)

Corundum (Al2O3)

Serpentinite (likely)

Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, chrysotile), commonly with magnetite and minor chlorite/talc

Veined Limestone

Sedimentary Calcite-Veined Rock (CaCO3)

Peacock Ore

Bornite (Cu5FeS4) or Chalcopyrite treated with acid

River Cobble (Basalt or Greywacke)

Extrusive Mafic Igneous Rock (likely Basalt)

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Almandine Garnet in Schist

Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist

Weathered iron-stained quartzite or sandstone cobble

Quartzite (quartz-rich rock), possibly ferruginous sandstone

Chert (and associated Sedimentary rocks)

Microcrystalline Silica (SiO2)

Weathered serpentinite (likely serpentine-rich rock)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, with possible magnetite and accessory minerals

Quartz Veined Rock (Likely Graywacke or Quartzite)

Silicon Dioxide (SiO2) veins in Metasedimentary matrix

Sapphire

Corundum (Al2O3)

Chert (with Epidote/Quartz veining)

Cryptocrystalline silica (SiO2) with Epidote/Quartz inclusions

Veined basalt (likely basalt with quartz/calcite vein)

Basalt, aphanitic mafic volcanic rock; vein minerals likely quartz (SiO₂) or calcite (CaCO₃)

Sandstone (likely Siltstone variety)

Arenite / Siltstone (primary mineral SiO2)

Emerald (Tumbled Beryl)

Beryllium Aluminum Silicate (Be3Al2Si6O18) with Chromium/Vanadium impurities

Slate

Slate (Foliated Metamorphic Rock)

Quartz-rich quartzite or silicified stone

Quartzite; predominantly microcrystalline quartz (SiO₂), with minor iron-oxide staining and possible feldspar/clay impurities

Quartz-bearing iron-rich rock, possibly quartzite or hydrothermal breccia

Quartz (SiO₂) with iron oxides/hydroxides, likely limonite/goethite; exact host rock is uncertain from the photograph

Venetian Gold Granite

Phaneritic Felsic Igneous Rock (Granite)

Quartzite

Quartzite (primarily SiO2)

Quartzite

Quartzite