Industrial Byproduct

Agate

Silicon Dioxide (Chalcedony), SiO2

River Pebble (Quartzite/Chert)

Quartzite with inclusions (SiO2)

Quartzite

Quartzite (SiO2)

Porphyritic Andesite

Andesite (Intermediate Volcanic Rock)

Pumice

Pumiceous volcanic glass

Pumice

Pumicite

Quartzite

Quartzite (SiO2)

Tumbled White Quartz

Silicon Dioxide (SiO2)

Gravel and Sediment Sample

Mixed clastic sediment

Diamond (or Lab-Grown Cubic Zirconia)

Carbon (C)

Silicon (Industrial Grade)

Elemental Silicon (Si)

Quartz Pebble

Silicon Dioxide (SiO2)

Faceted red ruby

Corundum (Al₂O₃), colored red by chromium

Red Garnet

Almandine Garnet (Fe3Al2(SiO4)3)

Opalite

Man-made glass (traditionally simulated Opal)

Tumbled black stone, likely black obsidian

Obsidian — volcanic glass, primarily SiO₂

Rough Diamond

Diamond (pure Carbon, C)

Aura Quartz (Coated Quartz)

Silicon Dioxide (SiO2) treated with metallic vapor

Gravel or Crushed Stone

Fragmented Aggregate Stone

Dark gray rock fragment

Indeterminate from image; possibly weathered basalt or fine-grained metamorphic rock

Black pebble, likely basalt

Basalt, fine-grained mafic volcanic rock; possibly weathered basaltic glass

Concretion or weathered iron-rich rock

Likely limonite/goethite-rich concretion; exact identification requires testing

Rounded pale-green pebble, likely serpentinite or altered basalt

Probable serpentinite (serpentine-group minerals) or weathered mafic rock; exact identification requires testing

Polished dark pebble, likely basalt

Basalt; fine-grained mafic rock dominated by plagioclase and pyroxene, commonly with olivine

Ironstone (Limonitic Shale)

Ferruginous Siltstone / Goethite-rich Sedimentary Rock

Potassium-Rich Silicate Clay (inferred from biological context)

Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)

Quartzite

Quartzite (primarily SiO2)

Sand Grain (Silica/Quartz Grain)

Silicon Dioxide (SiO2)

Small polished pebble, likely quartz or quartzite

Undetermined; possibly quartzite (quartz, SiO₂)

Banded agate (chalcedony)

Agate, a banded variety of microcrystalline quartz (SiO₂)

Red faceted gemstone, likely synthetic ruby

Corundum (Al₂O₃); ruby when red, possibly laboratory-grown

Small rounded pebble, likely porous volcanic rock

Possibly vesicular basalt or scoria; exact identification is not possible from the image alone

Pink tourmaline crystal (likely polished or rough-cut)

Elbaite, Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃

Red glassy gemstone, possibly garnet

Unidentified red transparent material; garnet group (X₃Y₂(SiO₄)₃) is a possibility

Red garnet-like faceted pendant

Possibly almandine garnet, Fe₃Al₂(SiO₄)₃; identification is uncertain from the image

Small rounded pebble; specific identification uncertain

Indeterminate lithic fragment; mineral composition cannot be determined from the image

Red gemstone ring; likely synthetic ruby or red glass

Undetermined from the image; ruby is corundum (Al₂O₃), while red glass is amorphous silicate

Likely pink-orange calcite (rough specimen)

Calcite, calcium carbonate (CaCO₃)

Faceted red gemstone, likely garnet

Most likely almandine garnet (Fe₃Al₂(SiO₄)₃); identification from the photo is tentative.

Small rounded rock (likely granite or gneiss)

Unidentified coarse-grained silicate rock; likely granitic composition

Ruby

Corundum (Al2O3 with Chromium trace)

Diamond (or Cubic Zirconia)

Carbon (C) / Cubic Zirconium Dioxide (ZrO2)