Synthetic Or Natural Fiber

Sandstone

Arenite (primarily SiO2)

Limonite (Iron Ore)

Hydrous ferric oxides (FeO(OH)·nH2O)

Coquina

Biogenic Limestone (Calcite, CaCO3)

Hematite

Iron(III) oxide (Fe2O3)

Smoky Quartz

Silicon Dioxide (SiO2)

Green Aventurine (Tumbled Quartzite)

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Granite

Granite (composed primarily of Quartz SiO2, Feldspar KAlSi3O8, and Mica K(Mg,Fe)3AlSi3O10(OH)2)

Diamond (Round Brilliant Cut)

Diamond (Pure Carbon, C)

Red Sandstone

Arenite (with Iron Oxide)

Green Aventurine

SiO2 (Silicon Dioxide with inclusions of Fuchsite mica)

Cobaltian Calcite (Cobaltoan Calcite)

Cobalt-bearing Calcite (Ca,Co)CO3

Green Aventurine

Silicon Dioxide (Quartz) with inclusions of Fuchsite mica (K(Al,Cr)2(AlSi3O10)(OH)2)

Green Aventurine

Aventurine Quartz (SiO2 with inclusions)

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite mica

Citrine

Silicon Dioxide (SiO2) with iron impurities

Amethyst

Silicon dioxide (variant with ferric iron impurities), SiO2

Smoky Quartz with Calcite/Quartz Veining

Silicon Dioxide (SiO2)

Amethyst

SiO2 (Silicon Dioxide with iron impurities and irradiation)

Citrine (Yellow Quartz)

Silicon Dioxide (SiO2)

Ferruginous Slag (Iron Smelting Byproduct)

Fused Silicate Scoria (Amorphous mixture of FeO, SiO2, and CaO)

Smoky Quartz Geode Slice

Silicon Dioxide (SiO2)

Lemon Quartz (Orizaba/Citrinated Quartz)

Silicon Dioxide (SiO2) with iron impurities/treatment

Orange Calcite (Cleavage Rhomb)

Calcite (Calcium Carbonate, CaCO3)

Citrine Quartz

Silicon Dioxide (SiO2)

Titanium-Coated Hematite (Aura Hematite)

Titanium-bonded Hematite (Fe2O3 with a Ti coating)

Amethyst (Tumbled)

Quartz (Silicon Dioxide, SiO2) with iron impurities

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Azurite and Malachite on Matrix

Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Shiva Lingam

Cryptocrystalline Quartz (Jasperiod Silicate with Iron Oxide inclusions)

Staurolite (Fairy Cross)

Staurolite (Fe2+2Al9Si4O23(OH))

Citrine (Iron-stained Quartz)

Silicon Dioxide (SiO2)

Rough Diamond

Native Carbon (C)

Titanium Aura Quartz (Bismuth-coated Druzy)

Silicon Dioxide (SiO2) with Titanium/Metal vapor coating

Native Copper with Malachite and Chrysocolla

Native Copper (Cu) with Malachite [Cu2CO3(OH)2] and Chrysocolla [(Cu,Al)2H2Si2O5(OH)4·nH2O]

Diamond (Princess Cut Faceted Gemstone)

Native Carbon (C)

Emerald

Beryl (Be3Al2(SiO3)6) with Chromium and/or Vanadium impurities

Yellow Quartz (Citrine Quartz or Yellow Jasper)

Silicon Dioxide (SiO2) with iron impurities

Diamond

Diamond (Pure Carbon, C)

Herkimer Diamond

Quartz (Silicon Dioxide, SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Black Diamond / Black Sapphire

Carbon (C) or Corundum (Al2O3)