TIMOTHÈQUE / CRYSTALS & MINERALS
Crystals & Minerals.
Gemstones, crystals, minerals, natural glass and objects shaped by the earth.
Quartz
Agate
SiO₂Banded chalcedony with layered colors and patterns.
Garnet
Almandine
Iron aluminum garnetCommon red garnet variety.
Feldspar
Amazonite
Microcline feldsparGreen to blue-green microcline feldspar.
Organic
Amber
Fossilized resinFossilized tree resin used as an organic gemstone.
Quartz
Amethyst
SiO₂Purple quartz colored mainly by iron-related color centers.
Quartz
Ametrine
SiO₂Bicolored quartz showing amethyst and citrine zones.
Zeolite
Analcime
Zeolite mineralZeolite mineral commonly forming trapezohedral crystals.
Silicate
Andalusite
Aluminum silicatePleochroic aluminum silicate mineral.
Garnet
Andradite
Calcium iron garnetGarnet species including demantoid.
Anhydrite
Angelite
Blue anhydrite trade nameTrade name for pale blue anhydrite.
Copper Silicate
Apachite
Copper Silicate mineralRare hydrated copper silicate mineral with a vivid blue color and silky, fibrous crystal aggregates. First discovered at the Christmas Mine in Arizona.
Phosphate
Apatite
Phosphate mineral groupApatite-group mineral used as a gemstone and collector specimen.
Silicate
Apophyllite
Apophyllite-group mineralCommon collector crystal often associated with zeolites.
Beryl
Aquamarine
Be₃Al₂Si₆O₁₈Blue to blue-green beryl.
Carbonate
Aragonite
Calcium carbonate mineralCalcium carbonate polymorph distinct from calcite.
Quartz
Aventurine
SiO₂Quartz with blue-toned mineral inclusions.
Carbonate
Azurite
Copper carbonate mineralDeep blue copper carbonate hydroxide.
Sulfate
Barite
Barium sulfate mineralDense sulfate mineral occurring in tabular crystals and rosettes.
Cyclosilicate
Benitoite
Barium Titanium Cyclosilicate mineralRare barium titanium silicate mineral known for its sapphire-blue color, triangular crystals, and exceptional dispersion. The state gemstone of California.
Mica
Biotite
K(Mg,Fe)₃AlSi₃O₁₀(OH,F)₂Dark iron- and magnesium-rich mica.
Quartz
Bloodstone
SiO₂Dark green chalcedony or jasper with red spots.
Calcite
Calcite
CaCO₃Common carbonate mineral known for strong cleavage and double refraction.
Quartz
Carnelian
SiO₂Orange to reddish chalcedony colored by iron oxides.
Sulfate
Celestite
SrSO₄Strontium sulfate known for pale blue crystals.
Quartz
Chalcedony
SiO₂Cryptocrystalline silica forming many familiar gem varieties.
Sulfide
Chalcopyrite
CuFeS₂Copper iron sulfide that can tarnish to colorful surfaces.
Silicate
Charoite
K(Ca,Na)₂Si₄O₁₀(OH,F)·H₂OPurple fibrous mineral known from Siberia.
Copper silicate
Chrysocolla
Copper silicate materialBlue-green copper-bearing material used as an ornamental stone.
Quartz
Chrysoprase
SiO₂Nickel-colored green chalcedony.
Sulfide
Cinnabar
HgSBright red mercury sulfide; handle specimens carefully and avoid dust.
Quartz
Citrine
SiO₂Yellow to orange quartz; much commercial citrine is heat-treated amethyst.
Oxide
Corundum
Aluminum oxide mineralVery hard aluminum oxide; gem varieties include ruby and sapphire.
Silicate
Danburite
Calcium borosilicateTransparent gemstone mineral with good hardness.
Gypsum/Barite
Desert Rose
Gypsum or barite rosetteRosette-shaped crystal aggregate formed in arid environments.
Pyroxene
Diopside
Chromium-bearing diopsideBright green chromium-bearing pyroxene gemstone.
Dumortierite
Dumortierite
Al₇BSi₃O₁₈A fibrous aluminum borosilicate mineral, typically found in deep blue to violet aggregates.
Beryl
Emerald
Be₃Al₂Si₆O₁₈Chromium- or vanadium-colored green beryl.
Silicate
Epidote
Calcium aluminum iron silicateGreen silicate mineral common in metamorphic rocks.
Halide
Fluorite
Calcium fluoride mineralColorful cubic mineral with perfect octahedral cleavage.
Sulfide
Galena
Lead sulfide mineralDense metallic lead sulfide with cubic cleavage; contains lead.
Silicate
Garnet
Garnet groupGroup of silicate minerals sharing a common crystal structure.
Glass
Goldstone
SiO₂Man-made glass containing reflective metallic crystals.
Beryl
Goshenite
Be₃Al₂Si₆O₁₈Colorless variety of beryl.
Garnet
Grossular
Calcium aluminum garnetGarnet species including tsavorite and hessonite varieties.
Quartz
Hawk's Eye
Chatoyant quartzBlue-gray chatoyant quartz, closely related to tiger's eye.
Beryl
Heliodor
Be₃Al₂Si₆O₁₈Yellow to golden beryl.
Oxide
Hematite
Iron oxide mineralIron oxide with a characteristic reddish-brown streak.
Zeolite
Heulandite
Zeolite mineralZeolite mineral occurring in tabular crystals.
Spodumene
Hiddenite
Green spodumeneGreen chromium-bearing spodumene.
Borate
Howlite
Calcium borosilicate hydroxideWhite porous mineral with gray veining; often dyed to imitate turquoise.
Tourmaline
Indicolite
Blue tourmalineBlue tourmaline variety.
Cordierite
Iolite
Gem cordieriteStrongly pleochroic gemstone variety of cordierite.
Pyroxene
Jadeite
NaAlSi₂O₆One of the two minerals traditionally called jade.
Quartz
Jasper
Patterned jasperJasper with landscape-like patterns.
Borate
Jeremejevite
Al₆(BO₃)₅(F,OH)₃A rare aluminum borate mineral that forms elongated prismatic crystals, often in pale blue or colorless varieties.
Organic
Jet
Fossilized woodOrganic gemstone formed from altered fossil wood.
Spodumene
Kunzite
LiAlSi₂O₆Pink to violet spodumene colored by manganese.
Silicate
Kyanite
Al₂SiO₅Aluminum silicate with directional hardness.
Feldspar
Labradorite
(Ca,Na)(Al,Si)₄O₈Plagioclase feldspar famous for labradorescence.
Pectolite
Larimar
NaCa₂Si₃O₈(OH)Blue pectolite variety from the Dominican Republic.
Igneous rock
Larvikite
Monzonitic rockNorwegian igneous rock showing blue feldspar reflections.
Rock
Lazurite
Na₇Ca(Al₆Si₆O₂₄)(SO₄)(S₃)·H₂OBlue rock composed mainly of lazurite with calcite and pyrite.
Mica
Lepidolite
K(Li,Al,Rb)₃(Al,Si)₄O₁⁰(F,OH)₂Lithium-rich mica commonly occurring in pegmatites.
Oxide
Magnetite
Fe₃O₄Strongly magnetic iron oxide mineral.
Carbonate
Malachite
Cu₂CO₃(OH)₂Green copper carbonate hydroxide with banded patterns.
Natural impact glass
Moldavite
SiO₂ (+ Al₂O₃)Green natural glass formed by a meteorite impact in central Europe.
Quartz
Mookaite
SiO₂Australian silicified sedimentary material sold as jasper.
Feldspar
Moonstone
(Na,K)AlSi₃O₈Feldspar showing adularescence.
Beryl
Morganite
Be₃Al₂(Si₆O₁₈)Pink to peach beryl colored by manganese.
Mica
Muscovite
Light micaSheet-forming mica with perfect basal cleavage.
Zeolite
Natrolite
Zeolite mineralNeedle-like fibrous zeolite mineral.
Amphibole
Nephrite
Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂Tough amphibole aggregate and one of the two traditional jades.
Volcanic glass
Obsidian
Volcanic glassNatural volcanic glass formed by rapid cooling of silica-rich lava.
Quartz
Onyx
SiO₂Parallel-banded chalcedony; black material is commonly dyed.
Silica
Opal
Hydrated amorphous silicaHydrated amorphous silica; precious opal can show play-of-color.
Glass
Opalite
SiO₂Trade name commonly used for opalescent man-made glass; not natural opal.
Feldspar
Orthoclase
Potassium feldsparCommon potassium feldspar mineral.
Organic
Pearl
Biogenic gemCalcium carbonate gem produced by mollusks; cultured pearls are common.
Olivine
Peridot
Gem olivineGem-quality olivine.
Fossil material
Petrified Wood
Silicified fossil woodFossil wood replaced or infilled by silica.
Quartz
Pietersite
SiO₂Brecciated chatoyant quartz material with swirling patterns.
Cyclosilicate
Poudretteite
Potassium Sodium Boron SilicateAn exceptionally rare potassium sodium beryllium silicate mineral, known for its delicate pink to purple coloration.
Quartz
Prasiolite
SiO₂Green quartz; much material is produced by heat treatment.
Silicate
Prehnite
Calcium aluminum silicateTranslucent pale green mineral often forming botryoidal aggregates.
Sulfide
Pyrite
FeS₂Metallic iron sulfide commonly forming cubes and pyritohedra.
Carbonate
Rhodochrosite
Manganese carbonatePink to red manganese carbonate, often banded.
Silicate
Rhodonite
Manganese silicatePink manganese silicate often crossed by dark manganese oxides.
Carbonate
Rosasite
CuZn(CO₃)(OH)₂A secondary copper zinc carbonate mineral, typically forming blue-green botryoidal, fibrous, or radiating aggregates on oxidized ore deposits.
Tourmaline
Rubellite
Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄Pink to red gem tourmaline.
Corundum
Ruby
Al₂O₃Red gem corundum colored primarily by chromium.
Oxide
Rutile
TiO₂Titanium dioxide mineral often found as needles in quartz.
Corundum
Sapphire
Gem corundumGem-quality corundum in colors other than red.
Sulfide
Schalenblende
A banded mineral aggregate composed mainly of sphalerite, commonly associated with wurtzite, marcasite, galena, and other sulfide minerals.
Tungstate
Scheelite
CaWO₄A calcium tungstate mineral known for its tetragonal crystals, often forming dipyramidal shapes and commonly exhibiting blue fluorescence under ultraviolet light.
Tourmaline
Schorl
Schorl tourmalineBlack iron-rich tourmaline, commonly schorl.
Zeolite
Scolecite
Zeolite mineralZeolite often forming radiating sprays of slender crystals.
Gypsum
Selenite
Gypsum varietyTransparent to translucent crystalline gypsum.
Sedimentary concretion
Septarian
Concretionary rockConcretion with mineral-filled cracks, commonly calcite and aragonite.
Chlorite
Seraphinite
Clinochlore varietyChatoyant green clinochlore trade material.
Carbon-rich rock
Shungite
Carbon-rich rockCarbon-rich Precambrian rock from Karelia.
Carbonate
Siderite
FeCO₃An iron carbonate mineral typically forming rhombohedral crystals or massive aggregates, often exhibiting yellowish brown to dark brown coloration.
Carbonate
Smithsonite
Zinc carbonate mineralZinc carbonate occurring in botryoidal and crystalline forms.
Sodalite Group
Sodalite
Na₈(Al₆Si₆O₂₄)Cl₂Blue sodium aluminum silicate, commonly mottled or veined with white calcite.
Feldspar
Spectrolite
Labradorite varietyTrade name for high-quality Finnish labradorite with vivid spectral colors.
Garnet
Spessartite
Manganese aluminum garnetOrange to reddish manganese-rich garnet.
Sulfide
Sphalerite
Zinc sulfide mineralZinc sulfide known for high dispersion in gem-quality material.
Oxide
Spinel
Magnesium aluminum oxideDurable gemstone occurring in many colors.
Silicate
Staurolite
Iron aluminum silicateMineral famous for cross-shaped twinned crystals.
Zeolite
Stilbite
Zeolite mineralZeolite commonly forming sheaf-like crystal aggregates.
Silicate
Sugilite
KNa₂Li₃(Fe, Mn, Al)₂Si₁₂O₃₀Purple potassium sodium lithium iron manganese silicate.
Feldspar
Sunstone
Feldspar gemstoneFeldspar showing aventurescence from reflective inclusions.
Oxide
Taaffeite
BeMg₃Al₈O₁₆An extremely rare magnesium beryllium aluminum oxide gemstone, commonly occurring in pink to violet shades.
Zoisite
Tanzanite
Ca₂Al₃(SiO₄)₃(OH)Blue-violet zoisite from Tanzania; heating is common.
Natural impact glass
Tektite
SiO₂Natural glassy objects formed by meteorite impacts.
Zeolite
Thomsonite
Na(Sr,Ca)₂Al₅Si₅O₂₀ ⋅7H₂OA zeolite mineral commonly forming radiating fibrous, acicular, or spherical crystal aggregates, sometimes displaying concentric color bands.
Zoisite
Thulite
Pink zoisitePink manganese-bearing zoisite.
Quartz
Tiger's Eye
SiO₂Fibrous quartz aggregate showing chatoyancy.
Titanite
Titanite
CaTiSiO₅A calcium titanium silicate mineral recognized for its wedge-shaped crystals, high dispersion, and brilliant luster.
Silicate
Topaz
Al₂SiO₄(F, OH)₂Hard gemstone mineral; blue topaz is commonly irradiated and heated.
Tourmaline
Tourmaline
Bicolor tourmalineTourmaline crystals with pink centers and green outer zones.
Garnet
Tsavorite
Ca₃Al₂(SiO₄)₃A vivid green, vanadium- or chromium-colored variety of grossular garnet, valued for its intense color and brilliance.
Phosphate
Turquoise
Copper aluminum phosphateOpaque blue-green gemstone; stabilization and treatment are common.
Rock
Unakite
Altered granite rockRock composed mainly of green epidote, pink feldspar, and quartz.
Phosphate
Variscite
Aluminum phosphate mineralGreen phosphate mineral used as an ornamental stone.
Tourmaline
Verdelite
Verdelite tourmalineGreen gem tourmaline.
Silicate
Vesuvianite
IdocraseSilicate mineral often found in skarns.
Phosphate
Vivianite
Iron phosphate mineralHydrated iron phosphate that can darken on exposure to light.
Molybdate
Wulfenite
PbMoO₄A lead molybdate mineral famous for its vivid orange to red coloration and distinctive thin tabular tetragonal crystals.
Zircon
Zircon
ZrSiO₄A naturally occurring zirconium silicate mineral, notable for its high refractive index, strong brilliance, and wide range of colors.
Silicate
Zoisite
Ca₂Al₃(SiO₄)₃(OH)Mineral species that includes tanzanite and thulite varieties.