Igneous, Sedimentary, Or Metamorphic (Mineral Based)

Almandine Garnet

Iron aluminum silicate (Fe3Al2(SiO4)3)

Garnet

Almandine formula: Fe3Al2(SiO4)3

Ferruginous Sandstone

Arenite with Iron-oxide cement

Green Aventurine (Carved)

Silicon Dioxide (Quartz variant) with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O(OH)2)

Corundum (Ruby Variety)

Corundum (Al2O3)

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock including secondary mineral infills)

Calcite

Calcite (Calcium Carbonate, CaCO3)

Quartz Pebble (often referred to as 'Sea Glass' or 'River Stone' when worn smooth)

Silicon Dioxide (SiO2)

Milky Quartz (Water-Worn Pebble)

Silicon Dioxide (SiO2)

Flower Agate

Silicon Dioxide (SiO2) - Variety of Chalcedony

Sandstone (with manganese staining)

Clastic sedimentary rock (primarily SiO2)

Red Garnet (Pyrope or Almandine)

Magnesium aluminum silicate (Mg3Al2(SiO4)3) or Iron aluminum silicate (Fe3Al2(SiO4)3)

Orthoclase Feldspar

KAlSi3O8 (Potassium aluminum silicate)

Shale (Beach-worn)

Laminated Pelite (primarily clay minerals and quartz)

Pyrite

Pyrite (Iron sulfide, FeS₂)

Citrine

Quartz (Silicon Dioxide - SiO2)

Quartz (possibly milky quartz or quartz with inclusions)

SiO2 (Silicon Dioxide)

Lepidolite in Quartz (or Lepidolite Ore)

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2) in Quartz (SiO2)

Granite

Granite (composed primarily of Quartz SiO2, Alkali Feldspar, and Plagioclase Feldspar)

Garnet Schist

Almandine Garnet in Mica Schist (Fe3Al2(SiO4)3)

Bloodstone (also known as Heliotrope)

Silicon Dioxide (SiO2) - variety of Chalcedony

Quartz (likely milky/gray variety)

Quartz (SiO₂)

Labradorite

Labradorite (Ca,Na)(Al,Si)4O8

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Ruby

Corundum (Al2O3 with Chromium traces)

Black Tourmaline

Schorl (Sodium iron aluminum borosilicate), NaFe3Al6(BO3)3Si6O18(OH)4

Ferruginous Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite inclusions

Moonstone (Green Moonstone / Garnierite)

Potassium Aluminum Silicate (KAlSi3O8) with inclusions of Garnierite

Smoky Quartz

Quartz (Silicon Dioxide) - SiO2

Yellow Quartz (Citrine Quartzite)

Silicon Dioxide (SiO2)

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Mixed Mineral Specimens

Mixed Silicates, Oxides, and Phosphates (SiO₂, Ca₅(PO₄)₃(F,Cl,OH), Na₈Al₆Si₆O₂₄Cl₂, etc.)

Citrine

Silicon Dioxide (SiO2)

Lemon Quartz (Orizaba/Citrinated Quartz)

Silicon Dioxide (SiO2) with iron impurities/treatment

Blue Sapphire

Corundum (Al2O3)

Magnetite

Magnetite (Fe3O4)

Smoky Quartz

Silicon Dioxide (SiO2)

Aventurine (Green Quartz)

Silicon Dioxide (SiO2) with inclusions of Fuchsite (Mica)

Smoky Quartz (Tumbled)

Smoky Quartz (Silicon Dioxide - SiO2)

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)