Granite

Emerald In Matrix (Quartz/Calcite)

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Sandstone

Arenite (composed primarily of SiO2)

Clear Quartz (Herkimer Diamond variant)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (Milky or Druzy Quartz)

Silicon Dioxide (SiO2)

Seashell Fragment (Aragonite/Calcite)

Calcium Carbonate (CaCO3) - Shell fragment

White Jade (Nephrite or Jadeite)

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2) or Jadeite (NaAlSi2O6)

Diamond

Diamond (pure Carbon, C)

Chert (specifically Yellow or River Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Amethyst (Tumbled)

Quartz (Silicon Dioxide, SiO2) with iron impurities

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Milky Quartz

Silicon Dioxide (SiO2)

Rose Quartz and Milky Quartz

Silicon Dioxide (SiO2)

Herkimer Diamond

Quartz (Silicon Dioxide) - SiO2

Chert (Flint)

Microcrystalline Quartz (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Anthracite Coal

Anthracite (Carbon-based metamorphic rock)

Chert (Flint variety)

Silicon Dioxide (SiO2)

Obsidian

Volcanic Glass (Amorphous Silica)

Olivine (Peridot)

Olivine (Magnesium Iron Silicate, (Mg,Fe)2SiO4)

Hematite

Iron(III) oxide (Fe2O3)

Amethyst

Silicon Dioxide (SiO2) containing iron impurities

Quartz (Druzy)

Silicon Dioxide (SiO2)

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Olivine in Basalt matrix

Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)

Tiger's Eye

Pseudomorph of quartz after crocidolite (SiO2 with iron oxide inclusions)

Clear Quartz

Silicon Dioxide (SiO2)

Pearl

Calcium Carbonate (CaCO3) with Conchiolin

Chert (varieties: Flint or Chalcedony)

Microcrystalline silica (SiO2)

Chert (Flint Pebbles)

Microcrystalline quartz (SiO2)

Beryl (Emerald Variety)

Beryllium aluminum silicate (Be3Al2(SiO3)6) with chromium/vanadium traces

Sandstone (Ferruginous)

Arenite (with Iron Oxide cement)

Jasper (Red/Brown Variety)

Jasper (Silicon Dioxide, SiO2 plus Iron Oxide impurities)

Beryl (Emerald Variety)

Beryllium Aluminum Silicate (Be3Al2(SiO3)6)

Cubic Zirconia

Cubic Zirconium Dioxide (ZrO2)

Basalt

Basalt (Mafic volcanic rock)

Obsidian

Obsidian (Volcanic Glass, primarily SiO2)

Quartzite

Quartzite (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Amethyst (Polished Point)

Crystalline Quartz (SiO2 with iron impurities)

Goldstone

Aventurine Glass (Man-made)

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)