Mineral

Raw Diamond (Rough Uncut)

Diamond (C - pure carbon)

Milky Quartz (Water-Worn Cobble)

Silicon Dioxide (SiO2)

Snowflake Obsidian

Volcanic glass with Cristobalite inclusions (70–75% SiO2)

Serpentine Schist with Quartz Vein

Serpentine Schist (a type of Metamorphic rock). The white band is likely Quartz (SiO2).

Schist

Mica Schist (Quartz-Muscovite-Biotite Schist)

Calcite

Calcite (CaCO3)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Bauxite (Concretionary)

Bauxite (Al(OH)3, AlO(OH))

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Fluorite

Calcium Fluoride (CaF2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Metasedimentary or Igneous matrix

Natural Gemstone Cabochons (Ruby, Moonstone, Emerald, Citrine)

Ruby (Al2O3:Cr), Moonstone (KAlSi3O8), Emerald (Be3Al2(SiO3)6:Cr), Citrine (SiO2)

Dendritic Siltstone (or Mudstone)

Siltstone with Manganese Oxide dendrites

Quartz (Milky/Clear Variety)

Silicon Dioxide (SiO2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

Fluorite

Calcium Fluoride (CaF2)

Milky Quartz Pebble with Chert

Silicon Dioxide (SiO2)

Quartz (Chert/Chunky Chalcedony)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Potassium Feldspar (Orthoclase)

KAlSi3O8

Obsidian

Volcanic Glass (SiO2 rich)

Fluorite

Fluorite (Calcium Fluoride - CaF2)

Quartz Pebble

Silicon Dioxide (SiO2)

River Quartz Cobble

Silicon Dioxide (SiO2)

Labradorite (Larvikite variety)

Plagioclase Feldspar (Na,Ca)(Si,Al)4O8

Pearl

Calcium Carbonate (primarily Aragonite and Calcite), CaCO3

Black Obsidian

Obsidian (Volcanic Glass)

Siltstone with iron staining

Siltstone (primarily SiO2 with FeO(OH) coatings)

Nephrite Jade

Ca2(Mg,Fe)5Si8O22(OH)2

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Potassium Feldspar and Quartz

KAlSi3O8 (Potassium Feldspar) and SiO2 (Quartz)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Limonite (Ironstone Concretion)

Hydrated iron(III) oxide-hydroxide (FeO(OH)·nH2O)

Glauconitic Sandstone

Greensand (Glauconite-bearing sandstone)

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

River Rock (Greywacke/Sandstone)

Lithic Wacke

Quartz

Silicon Dioxide (SiO2)

Blue Sapphire (likely costume glass imitation)

Corundum (Al2O3) with iron/titanium impurities

Greenstone (Metabaltic/Greenschist)

Chlorite schist / Meta-basalt

Amber / Fossilized Resin

Succinite / Fossilized Tree Resin