Mineral, Possibly Rock Fragment Containing A Mineral

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone Clast

Arenite (primarily SiO2)

Sandstone (Ferruginous/Red Sandstone)

Clastic sedimentary rock (primarily SiO2 with Fe2O3)

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with Fe2O3/FeO(OH) cement)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Glauconitic Sandstone (Greensand)

Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)

Limonite (Iron Ore)

Hydrous Iron Oxide (goethite, lepidocrocite)

Diorite

Diorite (intermediate intrusive igneous rock)

Dragon Blood Jasper

Epidote-containing Quartz Chalcedony (SiO2 with Ca2(Al, Fe)3(SiO4)3(OH))

Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)

There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).

Fossiliferous Limestone (Crinoidal)

Bioclastic Limestone (predominantly CaCO3)

Mixed Quartz and River Pebbles (Stone Collection)

Mixed assortment containing mainly Silicon Dioxide (SiO2)

Geode (Quartz)

Silicon Dioxide (SiO2)

Geode (Unopened)

Silica-rich concretion (SiO2)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Schist

Mica Schist

Diamond (Macled/Crystal fragment)

Carbon (C), isometric crystal system

Shale or Argillite

Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)

Larimar

Pectolite (Blue variety), NaCa2Si3O10(OH)

Limestone

Calcareous sedimentary rock (primarily CaCO3)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Granodiorite

Granodiorite (containing Quartz, Plagioclase, Orthoclase, Biotite/Hornblende)

Rough Emerald in Matrix

Beryl (Be3Al2Si6O18) with trace Chromium/Vanadium

Petrified Wood

Silicified Wood (primarily SiO2)

Gneiss (specifically a Granitic Gneiss specimen)

Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)

Milky Quartz Pebble (Iron-stained)

Silicon Dioxide (SiO2)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides

Agate (Geode nodule)

Cryptocrystalline Quartz (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Onyx (beads)

SiO2 (Cryptocrystalline Quartz)

Basalt

Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 with (Ca,Na)(Al,Si)4O8

Sandstone (Ferruginous)

Arenite (Fe-rich)

Porphyritic Basalt with Quartz Inclusions

Aphanitic Porphyritic Basalt

Smoky Quartz

Silicon Dioxide (SiO2)

Basalt with Olivine Phenocrysts

Porphyritic Basalt (containing Mg2SiO4 - Fe2SiO4)

Fuchsite on Quartzite

Muscovite (Chromium-bearing) K(Al,Cr)2(AlSi3O10)(OH)2

Barite

Barium Sulfate (BaSO4)

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2)

Conglomerate

Conglomerate (Sedimentary Clastic Rock)

Schist (Diamond Drill Core)

Mica Schist

Quartz (River Pebble)

Quartz (SiO₂ - Silicon Dioxide)