Mineral (Sedimentary Context)

Granitoid (Granite/Gneiss)

Granitoid silicate rock, primarily quartz and feldspar

Amethyst (Tumbled/Weathered Quartz)

Amethyst (SiO2 with iron impurities)

Black Onyx

Black Chalcedony (SiO2)

Schist (Biotite/Mica Schist)

Medium-grade regional metamorphic rock (rich in Phyllosilicates)

Gold (Elemental Metal)

Gold (Au)

Chert (Flint)

Silicon Dioxide (SiO2)

Shale or Slate with Quartz Veins

Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins

Seraphinite

Clinochlore (Mg,Fe)5Al(AlSi3O10)(OH)8 - specific variety for Seraphinite due to its fibrous inclusions and chatoyancy.

Ruby (in costume jewelry context)

Corundum (Al2O3) with Chromium impurities

Iron Slag

Anthropogenic Vitreous Silicate (Byproduct of Smelting)

Slag

Anthropogenic Vitrophyre (Iron or Smelting Slag)

Fuchsite

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

Green Quartzite (Aventurine-like)

Quartzite (primarily SiO2 with chromium-rich mica or chlorite inclusions)

Chert (often called Flint in this context)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (often called Flint in this context)

Silicon Dioxide (SiO2)

Serpentinite

Serpentinite (containing minerals of the Serpentine subgroup: Antigorite, Lizardite, and Chrysotile; formula (Mg,Fe)3Si2O5(OH)4)

Ferruginous Quartzite (also known as Ironstone or Gossan)

Ferruginous Quartzite with Goethite/Hematite staining

Opalite

Synthetic Glass, SiO2 base with metallic inclusions

Chert (Jasper or Flint variant)

Chert (composed of microcrystalline quartz, SiO2)

Arsenopyrite in Quartz Matrix

Arsenopyrite (FeAsS) with Quartz (SiO2)

Granite

Granite (a common type of Felsic Intrusive Igneous Rock)

Quartz (Druzy) in host rock

SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)

Onyx Marble (also commonly called Onyx)

Calcite (CaCO3), often with other mineral impurities

Sandstone with trace fossil

Sandstone, possibly with Skolithos or similar trace fossil

Fluorite (often referred to casually as 'Fluorspar' in industrial contexts)

Fluorite (CaF2)

Quartz (possibly milky quartz)

Quartz (Silica; SiO₂)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Gneiss

Gneiss (pronounced 'nice')

Chert (often called Flint in archaeological contexts)

Silicon Dioxide (SiO2)

Quartz

Quartz (SiO2 - Silicon Dioxide)

Tiger's Eye (often misinterpreted as Gold Ore in this context)

Pseudomorph of Quartz after Crocidolite (SiO2)

Pebble (likely a type of sandstone or quartzite pebble)

Clastic Sediment (specifically, a rudite-sized clast). If the pebble is composed of a specific rock type, its scientific name would be that rock type (e.g., 'Quartzite pebble', 'Granite pebble', 'Chert pebble'). Given its appearance, it is likely a metamorphic quartzite pebble or a hard sandstone pebble.

Petrified Wood

Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)

Rutilated Quartz

Quartz (SiO2) with Rutile (TiO2) inclusions

Weathered Volcanic Rock (possibly Rhyolite or Andesite Pebble)

Volcanic rock (e.g., Rhyolite or Andesite, specific identification would require thin section analysis or chemical assay). Mineral composition: Primarily feldspars (orthoclase and/or plagioclase), quartz (in rhyolite), micas, amphiboles, and sometimes pyroxenes.

Potassium-Rich Silicate Clay (inferred from biological context)

Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)

Granite (likely a river or beach pebble)

Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Pyrite

Iron Sulfide (FeS2)

Sandstone (Ferruginous)

Arenite (Fe-oxide cemented)

Fossil / Permineralized Bone

Tyrannosaurus rex fossil (Hydroxylapatite replaced by various minerals)

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)