Mineral Like (Anthropogenic)

Red Sandstone

Clastic Terrigenous Sedimentary Rock (composed mostly of SiO2 with Fe2O3)

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Sandstone Pebble

Arenite (primarily SiO2)

Tree Agate (Dendritic Agate)

Silicon Dioxide (SiO2) with Manganese/Iron inclusions

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Chert with Quartz/Calcite Vein

Microcrystalline Silica (SiO2)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Milky Quartz with Iron Oxide

Quartz (Silicon Dioxide, SiO2) with Limonite/Goethite staining

Arsenopyrite in Quartz/Host Rock

Arsenopyrite (FeAsS)

Ruby

Corundum (Al2O3)

Muscovite (White Mica)

Muscovite - Potassium aluminum silicate: KAl2(AlSi3O10)(F,OH)2

Quartz (Milky or Cloudy Quartz)

Silicon Dioxide (SiO2)

Sandstone River Cobble

Arenite (predominantly SiO2)

Fossilized Fish (Lepidotes)

Lepidotes sp. (Order: Lepisosteiformes)

Chrysocolla in Cuprite (Sonoran Sunrise)

Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O) (Chrysocolla) and Cu2O (Cuprite)

Banded Gneiss

Gneiss (variable mineral composition)

Granite

Granite (Felsic Plutonic Rock)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Malachite

Copper carbonate hydroxide [Cu2CO3(OH)2]

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Almandine Garnet

Almandine - Fe3Al2(SiO4)3

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Dyed Howlite

Borosilicate hydroxide (Ca2B5SiO9(OH)5)

Milky Quartz

Silicon Dioxide (SiO2)

Prehnite

Prehnite - Ca2Al(AlSi3O10)(OH)2

Pyrite

Iron Sulfide (FeS2)

Pyrite

Iron Disulfide (FeS2)

Moss Agate

Silicon Dioxide with inclusions (SiO2 + Fe/Mn/Mg)

Basalt

Mafic Igneous Rock

Sandstone

Clastic sedimentary rock (primarily SiO2)

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Schist

Mica Schist (formula variable based on mineral content, typically containing [K,Al,Fe,Mg,Si,O,H])

Obsidian and Phantom Quartz

Volcanic Glass (SiO2 + MgO + Fe3O4) and Crystalline Quartz (SiO2)

Black Marble

Recrystallized Calcite (CaCO3)

Quartz Vein (Iron-stained)

Silicon Dioxide (SiO2) with limonite/hematite staining

Basalt with Epidote (Greenstone)

Amygdaloidal Basalt (Ca2(Al, Fe)3(SiO4)3(OH) inclusions)

Amygdaloidal Basalt with Quartz/Zeolite Infill

Amygdaloidal Basalt (extrusive volcanic rock with SiO2 or CaAl2Si3O10·3H2O infill)

Chalcedony (specifically Agate or Common Opal variety)

Cryptocrystalline Silica (SiO2)