Man Made Material, Not A Natural Rock Or Mineral Specimen

Sandstone

Arenite

Druzy Quartz

Quartz (Silicon Dioxide, SiO2)

Amethyst cluster

Quartz, SiO₂; purple coloration is caused mainly by iron-related defects and natural irradiation

Sandstone (Quartz-rich Pebble)

Arenite (primarily SiO2)

Citrine (Heat-treated)

Silicon Dioxide (SiO2)

Foliated metamorphic rock, likely biotite schist

Mica schist, chiefly quartz, feldspar, and biotite mica

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Rhodonite-bearing metamorphic rock

Manganese-rich metamorphic rock, chiefly rhodonite (MnSiO₃), with quartz and manganese oxides

Citrine Geode Fragment

Silicon Dioxide (SiO2) with iron impurities

Coquina and Oyster Fossil Rock

Coquina limestone (Calcium Carbonate, CaCO3) containing fossilized Crassostrea / bivalve shells

Citrine Geode

Citrine (Silicon Dioxide, SiO2)

Tumbled metallic sulfide mineral specimen, likely pyrite-bearing ore

Likely pyrite (FeS₂) with associated sulfides and host rock; exact identification requires testing

Blue Kyanite

Kyanite (Al2SiO5)

Quartzite

Quartzite (SiO2)

Citrine (Raw)

Silicon Dioxide (SiO2) with iron impurities

Tumbled banded metamorphic stone

Likely banded gneiss or migmatitic gneiss; exact identification requires testing

Polished ocean jasper (orbicular jasper)

Microcrystalline quartz (SiO₂) with chalcedony, iron oxides, and assorted silicate inclusions

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Porphyritic Rhyolite (Llanite or similar)

Porphyritic Rhyolite / Quartz-Feldspar Porphyry

Tumbled copper-bearing rock, likely chrysocolla-bearing basalt or copper ore

Chrysocolla (hydrated copper phyllosilicate, approximately Cu₂H₂Si₂O₅(OH)₄·nH₂O) in a dark volcanic host

Weathered granitic or gneissic cobble

Likely altered granite/granodiorite; exact identification requires a fresh surface and testing

Granite or granitic gneiss

Felsic granitoid, chiefly quartz, feldspar, and mica; possibly weakly foliated gneiss

Tumbled rose quartz

Rose quartz (pink quartz), silicon dioxide, SiO₂

Asphalt (Bituminous Slate/Sandstone)

Asphaltum / Bituminous Rock

Chert (Nodule)

Microcrystalline or Cryptocrystalline Silica (SiO2)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2

Brecciated jasper/chalcedony

Silica-rich breccia composed mainly of microcrystalline quartz (SiO₂), with iron-oxide and possibly epidote or chlorite inclusions

Quartzite with Sandstone/Iron staining

Metamorphic Quartzite (SiO2)

Mica-rich schist

Muscovite–biotite schist, commonly quartz-bearing

Likely quartz-rich river pebble

Milky quartz or quartz-bearing granitic/gneissic fragment (SiO₂-dominant)

Diamond

Diamond (Native Carbon, C)

River Rock

Sedimentary Rock (various compositions)

Carnelian

Carnelian (SiO2 with Iron Oxide impurities)

Sandstone (Quartzose)

Arenite (Formula: SiO2 primary, with various cements)

Citrine Quartz

Silicon Dioxide (SiO2) with trace Iron impurities

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)

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

Quartz (SiO₂ - Silicon Dioxide)

Sodalite-bearing rock, likely sodalite-rich syenite or sodalite in feldspathic matrix

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂, with probable feldspar and accessory minerals

Diamond

Diamond (Pure Carbon, C)

Pink Granite

Granite (Felsic Plutonic Rock)

Granite

Granite (composed primarily of Quartz, Feldspar, and Mica)