Mineral Based Alloy (Anthropogenic)

Mica Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

Biotite (Black Mica)

Biotite (K(Mg,Fe)3AlSi3O10(OH)2)

Corundum (Sapphire/Ruby in Matrix)

Aluminium oxide (Al2O3)

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Muscovite Mica

Muscovite - KAl2(AlSi3O10)(OH)2

Celestite (Celestine)

Celestine (Strontium Sulfate, SrSO4)

Granite

Granite (a plutonic igneous rock composed primarily of quartz, feldspar, and mica)

Sandstone (Weathered Pebble)

Arenite (primarily SiO2)

Sandstone (Ferruginous)

Arenite (iron-rich)

Basalt with Iron Oxidation

Mafic Igneous Basalt

Vesicular Basalt with Quartz

Vesicular Basalt (SiO2 inclusions)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Iron Oxide staining)

Granite

Phaneritic Felsic Igneous Rock

Sandstone (Quartzite Pebble)

Arenite / Metamorphosed Sandstone (SiO2)

Diorite

Diorite (an intrusive igneous rock)

Mica Schist

Mica Schist (Complex Silicate Rock)

Granite

Phaneritic Igneous Rock (composed mostly of Quartz, Alkali Feldspar, and Plagioclase)

Flower Agate (Cherry Blossom Agate)

Chalcedony (SiO2) with Opaque Inclusions

Granite

Granite (Phaneritic Acid Igneous Rock)

Basalt with Vesicular Surface

Basalt (Mafic Extrusive)

Schist (Garnet-Mica Schist)

Garnet-Mica Schist (X-Y)3Z2(SiO4)3

Granite

Granite (composed primarily of Quartz SiO2, Orthoclase KAlSi3O8, and Plagioclase NaAlSi3O8 to CaAl2Si2O8)

Sandstone

Arenite (primarily Quartz, SiO2)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Basalt with Iron Oxidation

Extrusive Mafic Igneous Rock (composed of Plagioclase and Pyroxene)

Mica Schist

Mica Schist (predominantly Muscovite or Biotite sheet silicates)

Agate (specifically, multi-colored or pastel-dyed agate)

Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).

Schist

Mica Schist

Gneiss

Gneiss (high-grade metamorphic rock typically composed of quartz, feldspar, and mica)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary/Metamorphic Matrix

Quartz with Mica (Gneissic or Pegmatitic origin)

Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(F,OH)2)

Basalt (River Cobble)

Mafic Igneous Basalt (composed primarily of Plagioclase feldspar, Pyroxene, and Olivine)

Granite

Granite (Silicic Plutonic Rock)

Granite

Granite (Felsic Plutonic Rock)

Basalt with Vesicle/Vug

Basalt (Aphanitic Mafic Igneous Rock)

Granite

Granite (composed primarily of Quartz SiO2, Potassium Feldspar KAlSi3O8, and Plagioclase)

Granite

Phaneritic Felsic Igneous Rock

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Dendritic Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions

Labradorite

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

Mica (Biotite or Phlogopite variety)

Phyllosilicate (complex mineral formula involving K, Mg, Fe, Al, Si, and O)

Greisen (Quartz-Muscovite-Turretine Rock)

Greisen