Organic Gemstone (Not A Rock Or Mineral In The Traditional Sense, But Bio Mineralized Material)

Granitic Pegmatite

Coarse-grained Granite (KAlSi3O8 + SiO2)

Diamond

Diamond (pure carbon; C)

Petrified Wood

Silicified wood, primarily composed of Quartz (SiO2)

Iolite-bearing Gneiss (Cordierite)

Cordierite (Mg2Al4Si5O18) in Gneiss matrix

Black Onyx

Silicon Dioxide (SiO2) with cryptocrystalline structure

Banded Calcite (often sold as 'Mexican Onyx')

Calcite (Calcium Carbonate, CaCO3)

Basalt

Basalt (a mafic extrusive igneous rock)

Chert (Nodular Chert)

Microcrystalline Silica (SiO2)

Agate

Agate (a variety of Chalcedony, SiO2)

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz

Marble

Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)

Lapis Lazuli

Lapis Lazuli (a rock composed primarily of Lazurite (Na,Ca)₈[(S,Cl,SO₄,OH)₂|(Al₆Si₆O₂₄)], with varying amounts of Calcite, Pyrite, and Sodalite.)

Quartz (various varieties)

SiO₂ (Silicon Dioxide)

Diamond

Carbon (C), specifically a solid form of the element carbon with atoms arranged in a crystal structure called diamond cubic.

Citrine

Quartz (SiO2) - variety Citrine

Orange Calcite

Calcite (Calcium Carbonate, CaCO3)

Diamond

Carbon (C), specifically in an isometric crystal system.

Smoky Quartz

Smoky Quartz (SiO ₂)

Caliche (also known as hardpan, calcrete, kankar)

Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.

Amazonite

KAlSi3O8 (Potassium Aluminum Silicate) - a variety of Microcline Feldspar

Quartz (Crystal/Druzy Quartz)

Quartz (SiO₂)

Aventurine

Aventurine Quartz (SiO2 with inclusions)

Green Aventurine (likely)

Silicon dioxide (SiO2) with fuchsitemica inclusions

Diamond (Rough)

Diamond (Carbon, C)

Slag Glass

Amorphous Silica / Glass Slag

Amber

Succinite (Resinite)

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals, (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4)

Halite

Halite (NaCl)

Chert (or Flint)

Chert (a cryptocrystalline variety of quartz, SiO2)

Lapis Lazuli

Complex metamorphic rock containing Lazurite ((Na,Ca)8(AlSiO4)6(SO4,S,Cl)2), Calcite, and Pyrite

Conglomerate (Puddingstone)

Conglomerate (specifically, clastic sedimentary rock)

Granite (weathered pebble)

Granite (plutonic igneous rock)

Orthoclase Feldspar

KAlSi3O8 (Potassium Aluminum Silicate)

Black Tourmaline

Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)

Limonite (Iron Ore/Bog Iron)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Garnet

Garnet Group (complex nesosilicates with general formula X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+, V3+)

Gneiss

Gneiss (a metamorphic rock)

Carnelian (Chalcedony variety)

SiO2 (Silicon Dioxide)

Granite Cobble/Pebble

Granite

Slate

Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.

Tiger's Eye

Tiger's Eye (a variety of Chalcedony, which is a microcrystalline quartz with fibrous inclusions of oxidized crocidolite)

Orthoclase Feldspar

Orthoclase (KAlSi3O8)