Man Made Material

Chert

Chert (Microcrystalline Silica, SiO2)

Granite

Phaneritic Intrusive Igneous Rock (primarily composed of SiO2, Al2O3, K2O, Na2O)

Basalt (Vesicular)

Extrusive mafic igneous rock; primarily (Mg, Fe)2SiO4 (Olivine), CaAl2Si2O8 (Plagioclase Feldspar), and Pyroxene

Green Fluorite in Host Rock

Fluorite (Calcium Fluoride, CaF2)

River Quartzite Spheroid

Recrystallized Orthoquartzite (SiO2)

Serpentine

Serpentine group ((Mg, Fe, Ni, Al, Zn, Mn)3(Si, Al, Fe)2O5(OH)4)

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Diamond (or Cubic Zirconia imitation)

Carbon (C) - Native Element

Peridotite (Pyroxenite/Serpentinized Dunite)

Ultramafic Rock (consisting primarily of Olivine and Pyroxene)

Diamond

Diamond (Pure Carbon, C)

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Banded Sandstone

Arenite (composed primarily of Quartz: SiO2)

Stichtite in Serpentine (Atlantisite)

Mg6Cr2CO3(OH)16·4H2O (Stichtite) within Mg3Si2O5(OH)4 (Serpentine)

Red Sandstone

Arenite (primarily Quartz SiO2 with Hematite Fe2O3 cement)

Pink Quartz (Rose Quartz)

Silicon Dioxide (SiO2)

Iron Meteorite

Iron-nickel alloy (e.g., Kamacite, Taenite)

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Red Sandstone

Arenite (primarily Quartz with Hematite cement)

Jasper with Manganese Dendrites

Silicon Dioxide (SiO2) with Oxide Mineral Inclusions

Coquina / Fossiliferous Limestone

Fossiliferous Calcarenite (Calcium carbonate, CaCO3)

Olivine (often within Peridotite)

Magnesium iron silicate, (Mg,Fe)2SiO4

Olivine (Peridot)

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

Chert (with Manganese Dendrites)

Chert (Cryptocrystalline Quartz, SiO2)

Petrified Wood

Silicified Wood (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Dendritic Agate (Tree Agate)

Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions

Granite

Granite (Felsic Plutonic Rock)

Petrified Wood

Silicified Wood (primarily SiO₂)

Chert (Light Grey / Flint variant)

Cryptocrystalline Quartz (SiO2)

Chert (Yellow Jasper variant)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Rough Diamond

Diamond (Native Carbon), C

Diamond (Princess Cut)

Carbon (C)

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')

Calcite (Calcium Carbonate, CaCO3)

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood (SiO2)

Limonite (Iron Stone Concretion)

Limonite (Hydrous Iron Oxide) - FeO(OH)·nH2O

Petrified Wood

Silicified Wood (SiO2)

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (Milky or Iron-Stained)

Silicon Dioxide (SiO2)

Chert (specifically a Worked Flint/Knapped Flake)

Chert / Flint (Microcrystalline Quartz, SiO2)

Olivine (Peridot in gem form)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Flint

Chert (a form of cryptocrystalline quartz, chemical formula SiO₂)