This Appears To Be A Man Made Metallic Object, Likely Jewelry, Not A Natural Rock, Mineral, Or Geological Specimen.

Sandstone (Red/Brown Variety)

Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)

Granite

Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Opalite

Synthetic Glass (Simulated Opal)

Quartz

Silicon Dioxide (SiO2)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)

Raw Diamond (Rough Uncut)

Diamond (C - pure carbon)

Sandstone (Weathered Pebble)

Arenite (SiO2 primarily)

Basalt

Basalt (composition of plagioclase, pyroxene, and olivine)

Chalcedony (Agate/Quartz)

Silicon Dioxide (SiO2)

Sandstone (Quartzose)

Arenite (SiO2 principal)

Blue Cracked Quartz (Dyed Fire Crackle Quartz)

Silicon Dioxide (SiO2) with synthetic dye

Collection of Minerals and Ores

Various (e.g., Uraninite (U3O8), Carbon (C), Native Gold (Au), Hematite (Fe2O3), Galena (PbS), etc.)

Amethyst (Agate/Chalcedony variety)

Silicon Dioxide (SiO2) with iron impurities

Yellow Quartz (Citrine-colored Quartz Pebble)

Silicon Dioxide (SiO2)

Orange Quartzite / Carnelian Agate

Silicon Dioxide (SiO2)

Pyrite in Matrix (likely Quartz or Schist matrix)

Iron Sulfide (FeS2)

Quartz (Rock Crystal) with minor impurities

Quartz (SiO2)

Conglomerate

Conglomerate Rock (Paraconglomerate)

Basalt (Vesicular)

Basalt (Extrusive Volcanic Rock)

Jasper

Silicon dioxide / Chalcedony (SiO2)

Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)

Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.

Corundum

Corundum (Al2O3)

Sandstone (Quartz-rich)

Clastic sedimentary rock (SiO2 primary)

Synthetic Resin (Artificial Specimen)

Polyurethane or Polyester Resin

Green Glass (often marketed as 'Obsidian' or 'Green Quartz')

Amorphous Silica (SiO2) with copper or chromium additives

Quartz (Smoky/Milky variety)

Silicon Dioxide (SiO2)

Chert (Jasper variety) with Iron Oxide staining

Cryptocrystalline Quartz (SiO2) with Goethite/Limonite impurities

Blue Goldstone

Aventurine Glass

Cullet (Slag Glass)

Amorphous Silica (SiO2) with various metal oxide colorants

Unidentified Rock Fragment

Unknown

Agate (Polished Slice)

Banded Chalcedony (SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Magnetite (potentially as a Lodestone or within Ironstone)

Magnetite (Fe3O4)

Metal Alloy (Jewelry)

Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.

Sandstone (Greywacke)

Arenite / Clastic Sedimentary Rock

Vesicular Basalt (Scoria)

Basalt (Extrusive Igneous Rock)

Quartz (likely macrocrystalline variety)

Quartz (SiO₂)

Veined Pebble (likely a Quartz-Veined Pebble)

Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)

Sandstone (likely Quartzose type)

Clastic sedimentary rock (primarily SiO2)

Agate

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Quartz (likely Milky Quartz)

Quartz (SiO₂ - Silicon Dioxide)