Man Made Material (Simulated Mineral)

Sandstone (Ferruginous)

Arenite (with Iron Oxides)

Quartz (likely a macrocrystalline variety like milky quartz or smoky quartz, given the appearance in the image)

Quartz (SiO₂ - Silicon Dioxide)

Tumbled citrine quartz (likely heat-treated amethyst)

Quartz, SiO₂; crystalline variety citrine

Sandstone (Feldspathic / Arkose)

Sandstone (SiO2 with variable mineral grains)

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Chalcedony (likely common gray chalcedony)

Microcrystalline quartz, SiO₂

Polished hematite-rich ironstone

Hematite (Fe₂O₃), likely with magnetite and iron-rich jasper/goethite

Yellow jasper or polished yellow chalcedony

Microcrystalline quartz, SiO₂, likely iron-stained jasper/chalcedony

Red jasper (likely hematite-rich jasper)

Microcrystalline quartz (SiO₂) with iron oxides, chiefly hematite (Fe₂O₃)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Yellow-brown quartz/chalcedony fragment

Quartz, SiO₂; likely microcrystalline chalcedony with iron-oxide staining

Milky Quartz

Silicon Dioxide (SiO2)

Orange Aventurine

Quartz (SiO2) with Hematite or Goethite inclusions

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble with Hematite Inclusion

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Green Opal (Prase Opal)

SiO2 · nH2O (Hydrated Silicon Dioxide)

Quartz Pebble

Silicon Dioxide (SiO2)

Labradorite (Polished Sphere)

Labradorite ((Ca, Na)(Al, Si)4O8)

Citrine Quartz (Yellow Quartz)

Silicon Dioxide (SiO2) with iron impurities

Olivine (Peridot)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Amazonite

Microcline (K(AlSi3O8))

Labradorite

Labradorite ((Ca, Na)(Al, Si)4O8)

Chlorastrolite (Isle Royale Greenstone)

Chlorastrolite (Pumpellyite-(Mg,Fe2+): Ca2MgAl2(Si2O7)(SiO4)(OH)2∙H2O)

Quartz with Iron Staining

Silicon Dioxide (SiO2) with Hematite inclusions

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Milky Quartz (Water-worn pebble)

Quartz (Silicon Dioxide, SiO2)

Quartz Sand/Gravel

Silicon Dioxide (SiO2)

Rounded iron-rich pebble

Likely hematite/goethite-bearing quartzite or ironstone; exact identification requires testing

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron hydroxides

Granite or granitic rock fragment

Felsic intrusive igneous rock, typically quartz + feldspar + mica; exact species uncertain from the image

Diorite (Spotted)

Diorite (Intrusive igneous rock)

Sandstone

Arenite (lithic or quartz sandstone)

Milky quartz (rough quartz specimen)

Quartz, silicon dioxide (SiO₂)

Sandstone (specifically Lithic or Quartz Arenite)

Arenite (composed primarily of SiO2)

Stromatolite

Stromatolite (Cyanobacteria-formed Organo-sedimentary structure)

Sandstone

Arenite (SiO2 based)