Non Geological

Calcite crystal specimen

Calcite (CaCO₃)

Quartzite

Quartzite (SiO2)

Quartzite

Metamorphic Quartzite (SiO2)

Amber

Succinite (fossilized resin); C10H16O

Black Obsidian

Volcanic Glass (Amorphous Silicon Dioxide)

Limonite (Yellow Ochre)

Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)

Tumbled pink-and-gray quartzite (probable)

Quartzite; predominantly microcrystalline quartz (SiO₂), with iron-oxide and other mineral impurities

Tumbled green gemstone, likely dyed howlite or serpentine

Most consistent with dyed howlite (Ca2B5SiO9(OH)5); exact identification requires testing

Tumbled lapis lazuli

Lazurite-bearing calcite rock; lazurite approximately Na₃Ca(Si₃Al₃)O₁₂S

Black Obsidian

Volcanic Glass (predominantly SiO2)

Amber

Succinite (specific to Baltic amber), fossilized tree resin

Obsidian

Obsidian (Volcanic Glass)

Man-made Crystal (Lead Glass)

Lead oxide-doped Silica Glass (approx. SiO2 + PbO)

Mahogany Obsidian

Obsidian (Volcanic Glass with Hematite inclusions)

Siltstone River Pebble

Siltstone (primarily composed of silt-sized particles)

Tiny metallic mineral fragment, possibly native gold

Native gold (Au), unconfirmed; could also be pyrite or chalcopyrite

Conglomerate

Conglomerate (clastic sedimentary rock)

Quartzite

Quartzite (chiefly SiO2)

Polished leopard-skin jasper

Leopard-skin jasper; an opaque, microcrystalline quartz-rich rock, commonly with iron-oxide and volcanic/mineral inclusions

Milky quartz

Quartz (silicon dioxide, SiO₂), likely a massive vein-quartz specimen

Honey calcite (optical calcite)

Calcite — calcium carbonate, CaCO₃

Opalite

Man-made Synthetic Glass (Silicon Dioxide with metal additives)

Rose quartz

Quartz (SiO₂), pink variety

Siltstone with Quartz Vein

Siltstone (primarily SiO2, Al2O3, Fe2O3)

Black Obsidian

Volcanic Glass (Amorphous Silicon Dioxide SiO2)

Anthracite Coal

Anthracite (Carbon Content: 86%-97%)

Black Obsidian

Volcanic Glass (SiO2 with impurities)

Quartz Vein / Quartzite with Iron Oxide Staining

Silicon Dioxide (SiO2)

Obsidian

Obsidian (Volcanic Glass)

Obsidian

Volcanic glass (SiO2-rich)

Rainbow Obsidian

Volcanic glass (SiO2 - approximately 70% or more silicon dioxide)

Weathered sandstone cobble

Quartz-rich sandstone, primarily SiO₂ with clay/iron-oxide cement

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Obsidian

Volcanic Glass (Amorphous SiO2)

Likely calcite-rich limestone

Calcite (CaCO₃), probably micritic or fossiliferous limestone

Quartzite with Iron Oxide Vein

Metamorphic Quartzite (SiO2 with Hematite/Limonite impurities)

Quartzite

Quartzite (primarily SiO2)

Quartzite

Metamorphic rock predominantly composed of Quartz (SiO2)

Barite

Barium Sulfate (BaSO4)

Black obsidian (probable)

Volcanic glass; primarily SiO₂-rich rhyolitic composition

Rounded quartz-rich river cobble

Likely quartzite or quartz-rich sandstone (SiO₂-dominant), possibly weathered chert

Apache Tear (Obsidian)

Obsidian / Amorphous Volcanic Glass (primarily SiO2)