Anthropogenic (Man Made Material Processed By Nature)

Carved serpentine wing sculpture

Serpentine-group rock, chiefly antigorite/lizardite: Mg3Si2O5(OH)4

Dyed red crystal aggregate, likely quartz or salt

Uncertain; possibly dyed quartz (SiO₂) or halite (NaCl)

Blue Goldstone

Aventurine Glass (SiO2 with Cobalt/Copper inclusions)

Diamond

Carbon (C)

Milky Quartz / Chalcedony

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Coal (most likely Bituminous or Anthracite)

Coal (primarily composed of carbon with varying amounts of other elements)

Dyed Blue Agate Slice

Chalcedony (Silicon Dioxide, SiO2)

Wallboard/Drywall (Gypsum-based)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Tumbled amethyst

Amethyst, purple quartz (SiO₂), colored mainly by iron-related defects

Ruby in Matrix

Corundum (Al2O3)

Jasper

Silicon Dioxide (Microcrystalline Quartz / Chalcedony)

Bismuth Crystal

Bismuth (Bi)

Earthy iron-rich clay or weathered laterite

Hydrated iron oxides and clay minerals, commonly goethite/hematite with kaolinite or illite

Diamond Plate (Steel)

Alloyed Carbon Steel or Aluminum with 'Durbar' pattern

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Basalt

Basalt

Granite

Granite (Felsic intrusive igneous rock)

Sandstone (Red Flagstone)

Clastic sedimentary rock (primarily Quartz - SiO2)

Red coral earrings

Corallium rubrum or related precious coral (calcareous coral skeleton; primarily aragonite, CaCO₃)

Goldstone

Avventurina (Cu + SiO2 glass)

Marble

Metamorphic carbonate rock (Calcite/Dolomite)

Tumbled quartz crystal

Quartz (silicon dioxide, SiO₂)

Red Granite

Phaneritic Felsic Igneous Rock

Ferruginous Slag (Iron Smelting Byproduct)

Anthropogenic Vitreous Silicate (often containing Fayalite: Fe2SiO4)

Iron Slag

Ferrous Slag (complex silicate and oxide byproduct)

Chert (Flint)

Silicon Dioxide (SiO2)

Green Glass Cullet / Recycled Glass

Amorphous Silicon Dioxide (SiO2) with various metal oxides

Tumbled carnelian (likely dyed chalcedony)

Microcrystalline quartz, SiO₂; chalcedony variety, orange-red coloration from iron oxides

Unidentified gray stone/concrete-like fragment

Indeterminate; likely a fine-grained carbonate or cementitious geological fragment

Dyed Agate

Silicon Dioxide (SiO2) with synthetic dyes

Weathered limestone or concrete-like calcareous rock

Limestone; predominantly calcite (CaCO₃), possibly containing dolomite and silicate impurities

Likely quartz-rich rock fragment

Quartz (SiO₂), possibly a fragment of quartzite or silica-rich slag

Milky quartz with iron staining

Quartz (silicon dioxide, SiO₂), likely massive or vein quartz

Cobalt Glass Slug (Man-made Glass)

Amorphous Silica with Cobalt Oxide (SiO2 + CoO)

Gold-bearing quartz vein fragment (probable placer gold specimen)

Quartz (SiO₂) with probable native gold (Au) and iron-oxide staining

Jasper

Microcrystalline Quartz (SiO2)

Aura Quartz (Anomalously Coated Quartz)

Silicon Dioxide (SiO2) treated with vaporized metals

Silicon Carbide (Carborundum)

Silicon Carbide, SiC

Black obsidian bead bracelet

Obsidian — natural volcanic glass, chiefly silicic SiO₂-rich composition

Chert (White Chert/Flint)

Microcrystalline Quartz (SiO2)

Chert (variations include Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)