Mineral Like Byproduct

Malachite

Copper carbonate hydroxide Cu2CO3(OH)2

Amethyst Quartz

Silicon Dioxide (SiO2) with iron impurities

Pegmatite (Granitic) with Tourmaline

Granitic Pegmatite (containing Schorl and Quartz)

Limonite (Iron Ore)

FeO(OH)·nH2O

Vesicular Basalt (or Porphyritic Scoria)

Vesicular Basalt

Limonite (Ironstone)

Limonite (Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O)

Limonite (Iron Ore)

Limonite (unstructured hydrated iron(III) oxide-hydroxides, often FeO(OH)·nH2O)

Sandstone Concretion

Clastic sedimentary rock (primarily Quartz SiO2 with mineral cement)

Bauxite

Bauxite (Al(OH)3, AlO(OH))

Clear Quartz

Silicon Dioxide (SiO2)

Granite

Felsic intrusive igneous rock

Fossil Snail

Gastropoda (fossilized)

Carved Sea Turtle Figurine (Aventurine / Quartz / Jasper)

Quartz variety (SiO2) / Polycrystalline Quartz Aggregate

Granitic Pegmatite

Granitic Pegmatite (principally Quartz, Feldspar, and Mica)

Malachite-Bearing Copper Ore

Cu2CO3(OH)2 (Malachite) in host rock

Limonite with Iron Inclusions

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

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Vanadinite

Vanadinite (Pb5(VO4)3Cl)

Ironstone Concretion

Siderite or Hematite Concretion

Botryoidal Goethite

Goethite (α-Fe3+O(OH))

Sedimentary Sandstone with Iron Oxide

Ferruginous Sandstone

Plume Agate or Moss Agate

Silicon dioxide (SiO2)

Obsidian

Amorphous volcanic glass (SiO2)

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Dyed Crackle Quartz

Silicon Dioxide (SiO2) with dye

Pegmatite

Granitic Pegmatite

Green Fluorite

Calcium Fluoride (CaF2)

Sandstone

Quartzose Sandstone / Lithic Sandstone

Sandstone (Red/Brown Sandstone pebble)

Arenite (SiO2 dominated sandstone)

Clear Quartz (Tumbled)

Silicon Dioxide (SiO2)

Gneiss

Gneiss (High-grade metamorphic rock)

Mica-rich Schist fragment

Mica Schist

Epidote

Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

Gneiss

Gneiss (High-grade metamorphic rock)

Lepidolite with Quartz

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2

Magnetite

Magnetite (Fe3O4)

Potassium Feldspar

K-Feldspar (KAlSi3O8)

Banded Gneiss (with possible weathered sulfide or iron staining)

Gneiss, potentially with iron oxide/hydroxide staining (e.g., limonite) or weathered sulfides

Sandstone

Arenite

Smoky Quartz

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Silicon Carbide (Carborundum)

Moissanite (SiC)