Jasper

Jasper (Cryptocrystalline variety of Quartz, SiO2)

sedimentary

Pumice

Vesicular volcanic glass

igneous

Smoky Quartz (Faceted Beads)

Silicon Dioxide (SiO2)

mineral

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

mineral

Precious Red Coral

Corallium rubrum (Calcium Carbonate, CaCO3)

Mineral (Organic Gemstone)

Red Jasper (possibly Red Coral or dyed Howlite)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

sedimentary

Red Coral (Precious Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

sedimentary

Pearl

Organic gemstone (Calcium carbonate - CaCO3)

mineral

Lapis Lazuli (polished cabochon/sphere)

Na8[Al6Si6O24]Sn with accessory minerals (Pyrite, Calcite)

metamorphic

Black Pearl (Tahitian Type)

Aragonite / Conchiolin composite (CaCO3)

mineraloid

Tahitian Black Pearl

Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3

mineral

Selenite

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

mineral

Pyrite

Iron Sulfide (FeS2)

mineral

Pyrite

Iron Sulfide (FeS2)

mineral

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2)

sedimentary

Sandstone (Quartzose)

Arenite (SiO2 based)

sedimentary

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

mineral

Greywacke (River Slikenside)

Greywacke (Lithic Sandstone)

sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (SiO2 with Fe2O3 oxides)

sedimentary

Granite

Phaneritic Plutonic Felsic Rock

igneous

Rhyolite

Rhyolite (Extrusive Felsic Igneous Rock)

igneous

Quartzite with inclusions

Metamorphosed Quartz-rich Rock (SiO2)

metamorphic

Gneiss

Gneiss

metamorphic

Conglomerate

Conglomerate (Clastic Sedimentary Rock)

sedimentary

Diorite (River Pebble)

Intermediate plutonic igneous rock

igneous

Basalt

Basalt (High-iron/magnesium silicate rock)

igneous

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

sedimentary

River Pebble (Gabbro or Dark Sandstone variety)

Mafic Intrusive Rock (Plagioclase Feldspar and Pyroxene)

igneous

Basalt

Basalt (Mafic Extrusive Igneous Rock)

igneous

Basalt

Mafic Igneous Rock

igneous

Chert (specifically Jasper/Flint)

Chert (SiO2)

sedimentary

Basalt

Basalt (composition: Plagioclase, Pyroxene, and Olivine)

igneous

Quartzite

Quartzite (primarily SiO2)

metamorphic

Greenstone

Metabasalt / Greenschist facies rock

metamorphic

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

sedimentary

Basalt

Basalt

igneous

Basalt

Extrusive mafic igneous rock

igneous

Basalt

Basalt (comprising Plagioclase feldspar, Pyroxene, and Olivine)

igneous

Granite

Granite (Phaneritic intrusive igneous rock)

igneous

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

mineral

Basalt

Basalt (principally composed of pyroxene and plagioclase feldspar)

igneous

Basalt

Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

igneous