Man Made Material (Anthropogenic 'Mineraloid')

Rose Quartz

Silicon Dioxide (SiO2)

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Mahogany Obsidian

Volcanic Glass with Hematite/Magnetite inclusions (SiO2 + Fe2O3)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified wood (Quartz, SiO2)

Sandstone (specifically Red Sandstone)

Arenite (SiO2 with Iron Oxide)

Granite

Plutonic felsic igneous rock

Milky Quartz with Mineral Inclusions

Silicon Dioxide (SiO2)

Quartzite Pebbles

Quartzite (SiO2)

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Quartzite

Quartzite (primarily SiO2)

Quartzite

Quartzite (primarily SiO2)

Quartzite Pebble

Quartzite (primarily SiO2)

Sandstone (Ferruginous)

Arenite (Fe-rich)

Pyrite

Iron Sulfide (FeS2)

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Yellow Quartzite

Quartzite (SiO2)

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Quartzite Pebble

Quartzite (primarily SiO2)

Quartzite (River Cobble)

Quartzite (SiO2)

Moss Agate / Carnelian Agate

Silicon Dioxide (SiO2) with iron and manganese inclusions

Sandstone

Arenite (composed primarily of SiO2)

Rose Quartz

Silicon Dioxide with trace elements (SiO2 + Ti, Fe, or Mn)

Chert (Yellow Jasper/Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Serpentinite

Serpentinite (composed mainly of Group: Serpentine; (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Milky Quartz

Silicon Dioxide (SiO2)

Chert (Quartz)

Microcrystalline Silica (SiO2)

Schist

Mica Schist (Medium-grade metamorphic rock)

Plagioclase Feldspar

NaAlSi3O8 – CaAlSi2O8 (Sodium-Calcium Aluminum Silicates)

Sandstone Clast

Arenite (primarily SiO2)

Sandstone

Arenite (composed primarily of SiO2)

Limestone

Calcium Carbonate (CaCO3)

Quartzite

Quartzite (SiO2)

White Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Iron Oxide cement)

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Ferruginous)

Arenite with Iron Oxide (Fe2O3) cement