Man Made Object (Coin)

Quartz (Quarzite or Massive Quartz vein)

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Clear Quartz

Silicon Dioxide (SiO2)

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Amber / Copal

Organic resin, C10H16O

Sandstone (with potential iron-oxide staining)

Arenite (primarily SiO2)

Bauxite

Bauxite (Mixture including Gibbsite Al(OH)3, Boehmite γ-AlO(OH), and Diaspore α-AlO(OH))

Milky Quartz

Silicon dioxide (SiO2)

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily Quartz with Fe2O3 staining)

Sandstone (Quartz-rich)

Arenite (SiO2 based)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Quartzite (River Pebble)

Metamorphosed Quartz Sandstone (primarily SiO2)

River Cobble (likely Quartzite)

Metamorphosed Sandstone (SiO2)

Chert (Flint nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Marble (White)

Metamorphosed Limestone (mainly CaCO3)

Satin Spar (Gypsum)

Hydrous Calcium Sulfate (CaSO4·2H2O)

Iron Ore (Limonite and Hematite)

Goethite/Limonite (FeO(OH)·nH2O) and Hematite (Fe2O3)

Sandstone (likely Quartzose Sandstone)

Arenite (composed primarily of SiO2)

Clear Quartz

Silicon dioxide (SiO2)

Fossiliferous Limestone

Fossiliferous Calclutite / Bio-calcarenite (CaCO3)

Clear Quartz crystals on a Matrix base (Geode fragment)

Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)

Gold (10K Alloy)

Aurum (Au) with alloying metals (Cu, Ag, Zn)

Quartz

Silicon Dioxide (SiO2)

Sandstone (likely Arkose or Quartz Sandstone)

Clastic sedimentary rock (primarily SiO2)

Shale

Fissile Siliciclastic Sedimentary Rock

Bituminous Coal

Organic sedimentary rock (humic coal)

Cloudy Quartz

Silicon Dioxide (SiO2)

Olivine (Peridot)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Olivine (Peridot)

Magnesium Iron Silicate ((Mg, Fe)2SiO4)

Basalt (Water-worn Pebble)

Basalt (Mafic Extrusive Igneous Rock)

K2 Azurite Granite / K2 Stone

Granite (igneous rock) with Azurite inclusions (mineral)

Granodiorite Core

Granodiorite

Chert (or possibly Flint)

SiO2 (Silicon Dioxide)

Gold Placer (Gold Flakes and Nuggets)

Native Gold (Au)

Basalt (Crushed Roadstone)

Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

Limestone

Calcium Carbonate (CaCO3)

Rose Quartz

Silicon dioxide (SiO2)