Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)

Carved Mottled Greenish-Yellow Crystal/Glass Object

Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.

Fancy Jasper

Jasper (Cryptocrystalline Quartz, SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) - variety of Chalcedony

Sandstone

Sandstone (principally SiO2/Silicon Dioxide)

Fossil coral limestone

Fossilized colonial coral, commonly tabulate or rugose coral in calcite-rich limestone (CaCO₃)

Quartz

Silicon Dioxide (SiO2)

Quartz vein / massive quartz

Quartz (SiO₂), likely milky quartz with iron-oxide and possibly chlorite inclusions

Geode with Quartz Crystal Cavity

Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix

Pearl

Calcium Carbonate (CaCO3)

Quartz-veined dark metamorphic rock

Likely quartz-bearing hornfels, amphibolite, or altered basalt; exact identification requires a fresh surface and tests

Petrified Wood

Silicified wood (principally SiO2)

Bauxite Ore

Hydrated aluminum oxides (e.g., Gibbsite Al(OH)3, Boehmite ̲̲̲̲AlOOH, Diaspore ̲̲̲̲AlOOH)

Sandstone (Ferruginous)

Clastic Sedimentary Rock (Sandstone)

Chert Nodule

Chert (Microcrystalline Silicon Dioxide, SiO2)

Quartz-rich breccia or silicified rock with metallic sulfide mineralization

Microcrystalline and crystalline SiO₂, likely quartz/chalcedony, with possible pyrite or other sulfides

African Turquoise (Jasper)

Quartz (SiO2) with impurities (Epidote/Amphibole)

Tumbled carnelian (orange chalcedony)

Carnelian, a microcrystalline variety of quartz (SiO₂)

Amber

Succinite (fossilized resin)

Fossilized Coprolite

Coprolite (fossilized feces)

Amber and Citrine Quartz

Succinite (Amber) and Silicon Dioxide (SiO2 / Citrine)

Gravel / Limestone Fragment

Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock

Iron-stained quartz vein rock

Quartz (SiO₂), with iron-oxide minerals such as hematite and goethite

Pearl

Calcium Carbonate (Aragonite) - CaCO3

Amazonite

Microcline (Potassium Feldspar), KAlSi3O8

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Moonstone

Orthoclase Feldspar ((K,Na)AlSi3O8)

Emerald

Beryl (Be3Al2(SiO3)6) with Chromium/Vanadium impurities

Quartz-rich breccia or altered granite fragment

Polymineralic quartz–feldspar rock, likely hydrothermally altered granite/pegmatite

Bloodstone (Heliotrope)

Silicon Dioxide (SiO2) with inclusions of Hematite or Iron oxide

Pearl (Biogenic Mineraloid)

Calcium carbonate (CaCO3) primarily as Aragonite

Gemstone jewelry ensemble

Likely mixed gemstone and glass-bead jewelry; exact stones cannot be determined from the image

Petrified Wood

Silicified Wood (SiO2)

Amazonite

Microcline feldspar (KAlSi3O8)

Quartz-rich iron-stained rock

Massive to drusy quartz (SiO₂) with iron-oxide coatings, likely limonite/goethite

Amber

Fossilized Tree Resin (C10H16O)

Nephrite Jade

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

Rough Ruby

Corundum (Al2O3 with Chromium impurities)

Amber

Succinicum (C10H16O)

Fossil coral limestone

Fossilized colonial coral, commonly tabulate or rugose coral, preserved in calcite (CaCO₃)

Fossilized bone fragment, possibly dinosaur or large mammal bone

Fossil bone; mineralized apatite (carbonate-fluorapatite), commonly Ca₅(PO₄)₃(F,OH)

Quartz-rich pegmatite or quartz vein rock

Mostly quartz (SiO₂), with probable feldspar and iron-oxide staining

Biotite-rich granite or gneiss fragment

Dark mica-bearing granitoid; likely quartz–feldspar–biotite rock