Mineral, Specifically A Rock Fragment

Chert (specifically a Worked Flint/Knapped Flake)

Chert / Flint (Microcrystalline Quartz, SiO2)

Limestone (specifically Bituminous or Carbonaceous Limestone)

Calcium Carbonate (CaCO3) with Organic Impurities

Jasper (specifically Oolitic or Brecciated Jasper)

Silicon Dioxide (SiO₂)

Limestone (specifically Tufa or Travertine)

Calcium Carbonate (CaCO3)

Puddingstone (specifically Gowganda Tillite or St. Joseph Island Puddingstone)

Jasper Conglomerate

Chert (specifically as a lithic artifact/projectile point)

Chert (Silicon dioxide, SiO2)

Milky Quartz (Quartz Vein)

Silicon Dioxide (SiO2)

Bauxite

Bauxite (Mixture of Hydrous Aluminum Oxides)

Diorite

Diorite (Intermediate intrusive igneous rock)

Vesicular Basalt with Epidote

Vesicular Basalt (Mg, Fe)2SiO4 with Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))

Agate Geode

Silicon Dioxide (SiO2)

Iron Meteorite (Individual)

Siderite (composed of Kamacite and Taenite minerals)

Granitic Pegmatite

Pegmatitic Granite

Coquina

Bioclastic Limestone (Coquina)

Not a rock

Not a rock

Not a rock

Not a rock

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Smoky Quartz

Silicon Dioxide (SiO2)

Basalt (Amygdaloidal)

Amygdaloidal Basalt

Shale

Fissile mudrock (composed primarily of clay minerals and quartz)

Agate Geode with Quartz Druzy

Chalcedony (SiO2) and Quartz (SiO2)

Coquina

Bioclastic Limestone (composed primarily of CaCO3)

Vesicular Basalt with Quartz/Chalcedony

Vesicular Basalt (primarily Plagioclase, Pyroxene, and Olivine with SiO2 infill)

Chert (Grey/Black variety)

Chert (Silicon Dioxide, SiO2)

Fossilized Oyster Shell

Gryphaea or Crassostrea fossil (Calcium Carbonate, CaCO3)

Sea Glass (specifically Frosted White)

Amorphous Silica (substance: Sodium-calcium silicate glass)

Quartz Geode

Silicon Dioxide (SiO2)

Rough Diamond

Pure Carbon (C)

Amethyst Quartz Druse

Silicon Dioxide (SiO2) with iron impurities

Amygdaloidal Basalt

Basalt with Secondary Mineral Infillings

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Shale

Shale (Lutite)

Red Siltstone (or Red Shale)

Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)

Quartz Druzy Geode

Silicon Dioxide (SiO2) - Crystalline Variety

Limonite (after Pyrite Pseudomorph)

Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)

Obsidian (Apache Tear)

Obsidian (Amorphous Volcanic Glass / SiO2 with impurities)

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

Shale

Argillaceous Rock

Diamond

Diamond (a metastable allotrope of carbon, C)

Quartz (on matrix)

Quartz (Silicon Dioxide, SiO₂)

Fossiliferous Limestone (Crinoidal)

Bioclastic Limestone (predominantly CaCO3)

Gneiss

Gneissic Metamorphic Rock (Mineral composition: Quartz, Feldspar, Amphibole/Biotite)