Industrial Byproduct (Anthropogenic Material)

Rough Star Sapphire (Corundum)

Al2O3 (Aluminum Oxide)

Basalt

Basalt (composition of Plagioclase feldspar and Pyroxene)

Almandine Garnet

Iron aluminum silicate (Fe3Al2(SiO4)3)

Milky Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Granitic Pegmatite

Pegmatitic Granite

Desert Rose

Gypsum (variety Selenite) or Barite, CaSO4·2H2O

Rough Ruby

Corundum (Al2O3 with Chromium impurities)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Chalcedony in Limestone Host Rock

Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)

Red Sandstone

Clastic Terrigenous Sedimentary Rock (composed mostly of SiO2 with Fe2O3)

Shiva Lingam

Cryptocrystalline Quartz (Jasproid/Jasper)

Bornite (Peacock Ore)

Bornite (Cu5FeS4)

Kunzite (Spodumene)

Spodumene (LiAlSi2O6)

Quartzite

Quartzite (primarily SiO2)

Sodalite

Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)

Quartz (Iron-stained or Ferruginous Quartz)

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Milk Quartz (with Iron staining)

Silicon Dioxide (SiO2)

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 predominantly)

Garnet (Almandine variety)

Almandine Garnet (Fe3Al2(SiO4)3)

Blue Sapphire (Synthetic or Man-made Glass Imitation)

Corundum (Al2O3) if natural; Lead-glass or Spinal if synthetic

Pegmatite

Pegmatitic Granite

Quartz with Iron Oxide Inclusions

SiO2 with Fe2O3 impurities

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Banded Agate (with possible Chalcedony layers)

Silicon dioxide (SiO2)

Milky Quartz with Iron Staining

Quartz (Silicon Dioxide, SiO2)

Sandstone (likely Iron-rich or Arkosic)

Arenite (SiO2 with FeO(OH) or Fe2O3 staining)

Quartz (Milky/Yellowish)

Silicon Dioxide (SiO2)

Orange Calcite

Calcite (Calcium Carbonate - CaCO3)

Diamond (or Cubic Zirconia)

Carbon (C) or Zirconium Dioxide (ZrO2)

Diamond (in jewelry setting)

Diamond (C - Carbon)

Granite (Phaneritic Igneous Rock)

Granite

Vanadinite

Lead Chlorovanadate - Pb5(VO4)3Cl

Diamond (in jewelry)

Diamond (Carbon, C)

Granitic Pegmatite

Coarse-grained Igneous Rock (Granitic composition: KAlSi3O8, SiO2)

Rough Ruby (Corundum) in Zoisite Matrix

Al2O3 (Aluminum Oxide) with Ca2Al3(SiO4)3(OH)

Red Jasper (possibly Brecciated)

Jasper (Silicon Dioxide, SiO2)

Jasper pebble

Jasper (Silicon Dioxide, SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Druzzy Quartz on Matrix

Silicon Dioxide (SiO2)

Anthracite Coal

Anthracite (Metamorphosed Coal)

Quartz (River Pebble)

Silicon Dioxide (SiO₂)