Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse man made byproduct (often mistaken for obsidian or emerald) specimens identified by the Rock Identifier community.
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pyrite
Iron Sulfide (FeS2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartzite (Iron-stained)
Quartzite (primarily SiO2)
Rhodonite
Manganese Inosilicate (MnSiO3), often with Ca, Fe, Mg, Zn
Red Sandstone
Arenite (ferruginous sandstone)
Quartz
Quartz (SiO2)
Quartzite (specifically an iron-stained or Carnelian-colored variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Blue Calcite
Calcite (CaCO3)
Massive Quartz with Host Rock
Silicon Dioxide (SiO2)
Pyrite on Quartz
Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)
Turquoise
Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O
Pyrite
Iron Sulfide (FeS2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Chert Nodule (River Cobble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Calcite
Calcium Carbonate (CaCO3)
Quartzite
Quartzite (Primary mineral: Quartz, SiO2)
Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with traces of titanium, iron, or manganese
Jasper with Hematite inclusions
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)
Granitic Gneiss
Gneiss (Polymetamorphic Granitic Gneiss)
Glaucophane-bearing Schist (Blueschist)
Blueschist (Glaucophane-Lawsonite Schist)
Diamond (Green tinted)
Carbon (C) with trace impurities or lattice defects
Quartzite
Quartzite (primarily SiO2)
Chert (often called Flint when dark or worked)
Cryptocrystalline silica (SiO2)
Quartzite
Quartzite (SiO2)
Metallic Ornament / Jewelry
N/A - This is an artificial object, not a geological specimen.
Red Jasper
Jasper (a variety of Chalcedony, SiO₂)
Jasper (Imperial Jasper style)
Silicon Dioxide (SiO2) with impurities
Native Gold (in earring form)
Gold (Au)
White Agate (Chalcedony)
Agate (Silicon Dioxide - SiO2)
Red Shale
Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)
Milky Quartz
Silicon Dioxide (SiO2)
Jasper with Quartz inclusion
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Yellow Agate
Agate (Microcrystalline Silicon Dioxide, SiO2)
Red Quartzite
Quartzite (SiO2 with iron oxide impurities)
Terrazzo (Synthetic Composite Rock)
Cementitious or Epoxy Resin-bound Aggregates
Limestone
Calcium Carbonate (CaCO3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)