Mineral (Silicate Variety)

Picture Jasper

Silicon Dioxide (SiO2) with impurities

Garnet (likely Pyrope or Almandine)

Garnet Group (complex nesosilicate minerals, e.g., Pyrope Mg3Al2(SiO4)3, Almandine Fe3Al2(SiO4)3, Spessartine Mn3Al2(SiO4)3, Grossular Ca3Al2(SiO4)3, Andradite Ca3Fe2(SiO4)3, Uvarovite Ca3Cr2(SiO4)3). The vivid red color in the image strongly suggests Pyrope or Almandine.

Limonite Geode / Ironstone Nodule

Hydrated Iron Oxide Hydroxide (FeO(OH)·nH2O)

Nephrite Jade / Epidote Pebble

Ca2(Mg,Fe)5Si8O22(OH)2 / Ca2Al2Fe3+(SiO4)(Si2O7)O(OH)

Garnet Beads

Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)

Small pale blue-gray rock fragment

Unidentified fine-grained silicate rock; image insufficient for a reliable species-level identification

Probable tumbled garnet

Garnet-group silicate, commonly almandine (Fe₃Al₂Si₃O₁₂)

Slag (Industrial Byproduct)

Anthropogenic Vitreous Silicate material

Green Jasper (with Quartz veining)

Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2

Basalt with Epidote (Flowerstone-like texture)

Amygdaloidal Basalt (silicate mineral inclusions)

Glauconitic Sandstone (or Greenstone)

Glauconitic Sandstone with Quartz

Glauconitic Sandstone

Glauconitic Quartz Arenite

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Tumbled serpentine

Serpentinite; chiefly antigorite, lizardite, and chrysotile, with possible magnetite and accessory minerals

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Serpentinite

Serpentinite (complex silicate mineral group (Mg,Fe)3Si2O5(OH)4)

Vein-bearing metamorphic rock, likely gneiss or schist

Banded silicate rock; likely quartz–feldspar–mica gneiss with a quartz vein

Tourmalinated Quartz / Tourmaline in Matrix

Silicate mineral group (Schorl / Quartz)

Charoite

Charoite (Complex silicate mineral rock)

Black Jasper

Black Jasper (Silicate mineral - SiO2)

Kaolinite (China Clay / Chalky Claystone)

Al2Si2O5(OH)4

Blue Zircon

Zirconium Silicate (ZrSiO4)

Jasper (Red/Yellow)

Silicon Dioxide (SiO2) with impurities

Rhodonite

Manganese Silicate (MnSiO₃)

Pink Rhodonite

Manganese Silicate (MnSiO3)

Iron Slag

Anthropogenic Ferro-silicate

Rhodonite

Manganese silicate (MnSiO3)

Weathered quartz- or feldspar-rich rock fragment

Indeterminate light-colored silicate rock; possibly quartz or feldspar in a granitic fragment

Feldspar (specifically Orthoclase or Plagioclase)

Potassium Aluminum Silicate (KAlSi3O8) or Sodium/Calcium Aluminum Silicate

Quartz Pebble

Silicon Dioxide (SiO2)

Jasper

Silicon Dioxide (SiO2) with iron and magnesium inclusions

Snowflake Obsidian

Vitreous volcanic silicate rock (SiO2) with Spherulite inclusions

Shale

Shale (clay-sized silicate minerals)

Jasper with Epidote

Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate (Ca2(Al,Fe)3(SiO4)3(OH))

Muscovite Mica

Muscovite (Potassium Aluminum Silicate Hydroxide Fluoride), KAl2(AlSi3O10)(OH,F)2

Blue Aventurine

Silicon Dioxide (SiO2) with inclusions of Dumortierite

Weathered light-colored rock, possibly quartz-rich granite or quartzite

Indeterminate; likely quartz–feldspar rock (granite) or quartzite

Polished brecciated jasper

Jasper, microcrystalline quartz (SiO₂), with iron-oxide and dark mineral inclusions

Glauconitic Sandstone

Greensand (Glauconite-bearing sandstone)

Small pale pebble, possibly quartz or feldspar

Unidentified silicate; appearance alone cannot distinguish quartz (SiO₂) from feldspar

Kaolinite (Kaolin)

Kaolinite (Al2Si2O5(OH)4)

Basalt with Magnetite inclusions

Basalt (Mafic silicate rock) potentially containing Magnetite (Fe3O4)