Not A Rock Or Mineral

Milky Quartz

Silicon Dioxide (SiO2)

Emerald in Matrix

Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities

Olivine/Peridot

Magnesium Iron Silicate (Mg,Fe)2SiO4

Amethyst (Rough)

Silicon Dioxide with iron impurities (SiO2)

Pink Opal

Amorphous Hydrous Silica (SiO2·nH2O)

Chalcedony (Botryoidal)

Silicon Dioxide (SiO2)

Specular Hematite

Specularite (Fe2O3)

Clear Quartz

Silicon Dioxide (SiO2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Quartz River Pebble

Quartz (Silicon Dioxide, SiO2)

Iron-stained Milky Quartz

Silicon Dioxide (SiO2) with iron oxide inclusions

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Schist (Biotite Schist)

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

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Basalt

Mafic volcanic rock (various silicate minerals including Pyroxene and Plagioclase)

Pebble (river rock/beach pebble)

Pebble (clast size class)

Chalcedony Nodule (Agate/Chert)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Quartzite

Quartzite (SiO2)

Basalt with Iron Oxidation

Amygdaloidal Basalt (silicate rock primarily plagioclase, pyroxene, and olivine)

Clear Quartz (Rock Crystal)

Quartz (Silicon Dioxide, SiO2)

Shale with Pyrite

Clastic sedimentary rock containing Iron Disulfide (FeS2)

Muscovite Mica (Golden/Yellow variety)

KAl2(AlSi3O10)(F,OH)2

Tiger's Eye (Unpolished)

Pseudomorph of Quartz after Crocidolite (SiO2)

Sandstone (Ferruginous)

Arenite (Fe-rich)

Basalt

Basalt (Mafic volcanic rock)

Quartz with Mica inclusions (likely Schist or Gneiss host)

Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(OH)2)

Sandstone

Arenite (primarily Quartz, SiO2)

Sapphire (Corundum)

Corundum (Al2O3)

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Sandstone (Quartzose Pebble)

Clastic Sedimentary Rock (Litharenite/Quartz arenite)

Jasper

Jasper (Cryptocrystalline Quartz; SiO2)

Aventurine

Quartzite with inclusions (SiO2 containing Fuchsite chrome mica)

Unakite

Epidotized Granite

Quartzite

Quartzite (SiO2)

Sandstone Cobble

Arenite (Secondary classification based on grain size)

Milky Quartz Vein with Iron Staining

Silicon Dioxide (SiO2)

Sandstone (Green/Yellow Siltstone variant)

Arenite or Siltstone (primarily SiO2 with mineral staining)

Basalt with Quartz/Feldspar Vein

Amygdaloidal Basalt with Plutonic intrusion (SiO2/KAlSi3O8)

Granite Pebble (Salt and Pepper Granite)

Felsic Intrusive Igneous Rock (Granite)

Banded Gneiss

Gneiss (High-grade Metamorphic Rock)