Not A Rock Or Mineral (Anthropogenic Material)

Kyanite

Kyanite (Al2SiO5)

Pyrite

Iron Sulfide (FeS2)

Chert (specifically Yellow/Honey Jasper variety)

Cryptocrystalline Quartz (SiO2)

River Stone / Pebble

Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)

Banded Calcite (often commercially sold as 'Mexican Onyx' or 'Honey Onyx')

Calcite (Calcium Carbonate, CaCO3)

Chlorastrolite (Isle Royale Greenstone)

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

Chert (varieties include Flint or Jasper)

Chert (cryptocrystalline quartz; SiO₂)

Quartz Veined Rock (Likely Graywacke or Quartzite)

Silicon Dioxide (SiO2) veins in Metasedimentary matrix

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Engineer Quartz/Quartzite

SiO2 (Silicon Dioxide with binders)

Basalt Porphyry

Porphyritic Basalt

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Extrusive volcanic rock)

Granite

Phaneritic Plutonic Igneous Rock (primarily composed of quartz, alkali feldspar, and plagioclase)

Siltstone with iron staining

Siltstone (primarily SiO2 with FeO(OH) coatings)

Amethyst Geode/Cluster

Quartz (SiO2) - variety Amethyst

Sandstone (with Limonite staining)

Arenite (primarily SiO2 with FeO(OH)·nH2O)

Mica (Muscovite)

Muscovite (KAl2(AlSi3O10)(OH)2)

Pyrite

Iron Sulfide (FeS2)

Olivine (Peridot)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Citrine Quartz (Yellow Quartz)

Silicon Dioxide (SiO2) with iron impurities

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Milky Quartz (Water-worn pebble)

Quartz (Silicon Dioxide, SiO2)

Amazonite

Microcline (K(AlSi3O8))

Quartz with Iron Staining

Silicon Dioxide (SiO2) with Hematite inclusions

Labradorite

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

Peridot (Olivine)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Schist

Mica Schist (primarily consisting of muscovite KAl2(AlSi3O10)(OH)2 or biotite K(Mg,Fe)3(AlSi3O10)(OH)2)

Red Sandstone

Ferruginous Sandstone (SiO2 dominated with Fe2O3 cement)

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)

Granite

Phaneritic Plutonic Felsic Rock

Shale

Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)

Glauconite (Glauconitic Sandstone)

Glauconite [(K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2]

Iron Meteorite

Siderite (Iron-Nickel Meteorite)

Fossiliferous Chert with Brachiopod Impression

Chert (SiO2) containing Brachiopoda fossil remains

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Sandstone or Limestone

Arenite or Calcareous Sedimentary Rock

Fish Fossil in Limestone

Lycoptera (likely) in Micritic Limestone

Amethyst

Amethyst (Silicon Dioxide - SiO2)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Pebble (Likely Basalt or Siltstone)

Clastic sedimentary rock or mafic volcanic rock