Mineral (Or Mineraloid If Microcrystalline)

Ruby (Corundum)

Corundum (Aluminum Oxide with Chromium), Al2O3:Cr

Rose Quartz

Rose Quartz (Silicon Dioxide, SiO2)

Fossilized Brachiopod

Phylum Brachiopoda (replaced by Calcite/CaCO3)

Amethyst

SiO2 (Silicon Dioxide) - Purple variety of Quartz

Sandstone

Arenite (SiO2 based with quartz grains)

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Hematite

Hematite, Iron(III) oxide (Fe2O3)

Sandstone (likely Quartz Sandstone)

Arenite (SiO2 based)

Sandstone (with minor quartz and possible clay components)

Clastic Sedimentary Rock (SiO2 dominated)

Sandstone with Tafoni Weathering

Arenite (SiO2 based)

Sandstone (likely Graywacke or Arkose variant)

Clastic Sedimentary Rock (SiO2 based)

Epidosite (Unakite-related)

Epidosite (predominantly Epidote, Ca2(Al2,Fe3+)(SiO4)3(OH))

Druzy Chalcedony/Quartz on Fluorite core

Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Vesicular Basalt (Scoria)

Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

Yellow Calcite

Calcium Carbonate (CaCO3)

Sandstone

Arenite (primarily SiO2)

Copper-bearing Quartz (likely Malachite on Quartz matrix)

Cu2CO3(OH)2 (Malachite) on SiO2 (Quartz)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Carnelian Agate

Silicon Dioxide (SiO2) - variety of Chalcedony

Quartz (Milky or Iron-stained)

Quartz (Silicon Dioxide, SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

Yellow Quartz Pebble

SiO2 (Silicon Dioxide)

Gold Nugget

Native Gold (Au)

Sandstone (Quartzite Pebble)

Arenite (primarily SiO2)

Granitic Pegmatite

Pegmatite (composed primarily of Quartz, Feldspar, and Muscovite mica)

Calcite

Calcium Carbonate (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Mica Schist

Mica Schist (contains Muscovite/Biotite, Quartz)

Sandstone

Arenite (composed primarily of SiO2)

Feldspar (Orthoclase)

Potassium Feldspar (KAlSi3O8)

Milky Quartz

Silicon Dioxide (SiO2)

Orange Calcite

Calcium Carbonate (CaCO3)

General Rock and Mineral Collection (Center: Angelite / Blue Anhydrite)

Anhydrite (Calcium Sulfate, CaSO4)

Sandstone (Pebble)

Clastic sedimentary rock (SiO2 primary)

Ferruginous Sandstone

Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)

Tiger's Eye (Small Polished Bead)

Pseudomorph of Quartz after Crocidolite (SiO2)

Milky Quartz Pebble

Quartz (Silicon Dioxide - SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Green Aventurine

Aventurine Quartz (SiO2 with inclusions of Fuchsite mica)