Not A Natural Rock

Black Onyx

Cryptocrystalline Quartz (SiO2)

Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)

There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).

Dyed Aura Quartz

Silicon Dioxide (SiO2) with metallic coating

Smoky Quartz

SiO2 (Silicon Dioxide)

Goldstone (Red/Brown)

Aventurine Glass (SiO2 with Copper inclusions)

Diamond

Diamond (C)

Snowflake Obsidian

Volcanic Glass (SiO2 + impurities)

Man-made Green Quartz (Lab-grown or Treated)

Silicon Dioxide (SiO2) with artificial coloration

Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)

Quartz (SiO₂ - Silicon Dioxide)

Shale

Shale (fine-grained clastic sedimentary rock)

Citrine (likely Heat-Treated Amethyst)

Silicon Dioxide (SiO2)

Sandstone (likely a river or beach pebble)

Sandstone (a clastic sedimentary rock)

Obsidian

Obsidian (Volcanic Glass, SiO2 + impurities)

Red Swirl Beads (Likely Resin or Glass, simulating Red Jasper or Agate)

N/A (for the beads as pictured); Red Jasper: SiO2 (Chert variety); Red Agate: SiO2 (Chalcedony variety)

Shungite

Carbonaceous rock (primarily amorphous carbon)

Grey Slate

Foliated Metamorphic Rock (formed by low-grade regional metamorphism of shale or mudstone)

Metal Alloy (Likely Pewter or Sterling Silver)

Not a natural geological specimen; composed of refined metals. If pewter, it's a tin-based alloy. If sterling silver, it's 92.5% silver and 7.5% other metals (usually copper).

Blue Goldstone

Synthetic Avanturine Glass (or Aventurine Glass)

Black Obsidian

Obsidian, volcanic glass (Amorphous SiO₂)

Sapphire (likely blue synthetic sapphire or blue glass in a ring)

Corundum (Al₂O₃), specifically the blue variety due to trace amounts of iron and titanium impurities. If synthetic, it would still be Al₂O₃.

Turquoise (beads)

Turquoise; CuAl6(PO4)4(OH)8·4H2O

Moldavite

Moldavite (Siliceous vitreous substance)

Citrine

Silicon Dioxide (SiO2) with ferric iron impurities

Shale (possibly)

Shale (fine-grained clastic sedimentary rock)

Cullet (Slag Glass)

Amorphous Silica (Industrial byproduct)

Limonite

FeO(OH)·nH2O (Hydrated iron oxide)

Diamond

Diamond (Carbon, C)

Not a geological specimen

N/A (man-made object)

Citrine Quartz

Quartz (SiO2) - specifically, a variety of macrocrystalline quartz

Goldstone

Aventurine Glass (Man-made)

Demantoid Garnet on Matrix

Demantoid (variety of Andradite Garnet) - Ca3(Fe3+)2(SiO4)3

Smoky Quartz Cluster

Quartz (Silicon Dioxide) - SiO2

Citrine Quartz

Citrine (Silicon Dioxide, SiO2)

Goldstone (Red)

Aventurine Glass (SiO2 + Cu)

Chert Geode with Quartz Druzy

Microcrystalline Quartz (SiO2) with macrocrystalline Quartz

Quartzite Pebble

Quartzite (primarily SiO2)

Sandstone

Quartz Arenite (a common type of sandstone, given the appearance), Arkose, Greywacke (depending on mineralogy)

Snowflake Obsidian

Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)

Man-made Crystal (Lead Glass)

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

Orange Quartzite

Quartzite (primarily SiO2 with Hematite impurities)

Shungite

Shungite (Amorphous Carbon)

Quartz (Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)