Mixed (Sedimentary, Igneous, And Metamorphic)

Labradorite

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

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Banded River Rock / Gneiss (highly weathered)

Gneiss

Milky Quartz

Silicon Dioxide (SiO2)

Banded Gneiss (River Cobble)

Gneiss (a high-grade metamorphic rock)

Pyrite in Matrix (Gold-colored Chalcopyrite or Pyrite)

Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)

Quartz with Mica/Host Rock

Silicon Dioxide (SiO2) with Phyllosilicates

Spessartine Garnet

Manganese aluminum silicate (Mn2+3Al2(SiO4)3)

Citrine

Silicon Dioxide (SiO2)

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

Milky Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Rough Citrine Quartz

Citrine (Silicon Dioxide, SiO2 with iron impurities)

Marble

Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).

Biotite / Black Mica

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

Blue Sapphire (in a faceted jewelry setting)

Corundum (Al2O3) with trace Iron and Titanium

Muscovite Mica

Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2

Tiffany Stone

Bertrandite (Be4Si2O7(OH)2) mixed with Fluorite (CaF2), Opal, and Chalcedony

Diopside (likely Chromian Diopside)

Diopside, part of Clinopyroxene family of inosilicates. Chemical formula: CaMgSi2O6. The green variety is often Chromian Diopside due to chromium impurities.

Iolite (Cordierite)

Cordierite (Magnesium Aluminum Silicate), Mg2Al4Si5O18

Marble

Metamorphosed Limestone/Dolomite

Osumilite in Granite Matrix

(K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30

Epidote with quartz/feldspar

Epidote, Ca2(Al,Fe)3(SiO4)3(OH)

Epidote

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

Schist

N/A (a rock type, not a mineral formula)

Shale or Argillite

Shale (sedimentary) / Argillite (metamorphic)

Rose Quartz

Rose Quartz (SiO2)

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Calcite (Yellow/Orange variety - sometimes called Honey Calcite)

Calcite

Biotite Mica

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

Banded Rock (likely Quartz-rich)

Uncertain, likely a Metamorphic Rock (e.g., Gneiss or Schist) with prominent Quartz and other minerals

Moonstone

Adularia (orthoclase feldspar variety)

Schist

Schist (various mineralogical compositions including mica, chlorite, talc, etc.)

Plagioclase Feldspar (specifically Albite/Oligoclase)

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

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Epidote

Epidote (Ca2(Al2,Fe3+)AlSi3O12(OH))

Kyanite

Kyanite (Al2SiO5)

Quartz (likely a weathered/tumbled piece)

Quartz (SiO₂)

Sunstone

Feldspar (variety Oligoclase or Labradorite), (Ca,Na)(Al,Si)4O8