Guide to stones from A to Z
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One page per stone: what it really is as a mineral, the symbolism that tradition associates with it, how to care for it, how to recognise it and avoid imitations. Browse the alphabetical index or search for the name of the stone that intrigues you.
A B C D E F G H I J K L M N O P Q R S T U V W Z É Œ
A
AgateAgate is a banded chalcedony, a quartz with microscopic grains. Here are its varieties, its traditional symbolBlue lace agateBlue lace agate is a pale blue and white chalcedony with wavy bands like lace, coming mainly from Namibia. OriBotswana agateBotswana agate is a small nodular agate with very fine grey, pink and lavender bands, from basalts in BotswanaFire agateFire agate is a brown chalcedony whose very thin layers of iron oxide create flashes of red, orange and green.Dendritic agateDendritic agate is a pale chalcedony decorated with black fern- or tree-like patterns. The patterns are made oCrazy lace agateCrazy lace agate is a Mexican vein agate with tangled patterns in white, red, yellow or grey. Origin, symbolisMoss agateMoss agate is a translucent chalcedony with green moss-like inclusions. It is not banded. Origin, symbolism anBlack agateBlack agate is a glossy black chalcedony, almost always dyed or heated. Origin, traditional symbolism, how it Green agateGreen agate is a banded green chalcedony. Bright commercial green is very often dyed; natural green exists butAquamarineAquamarine is the pale blue to blue-green variety of beryl, the stone of March and the sailors' stone. Origin,AlexandriteAlexandrite is a rare variety of chrysoberyl that shifts from blue-green in daylight to red under incandescentAmazoniteAmazonite is a green-blue feldspar (microcline) streaked with white, used in jewellery for more than 3,000 yeaAmberAmber is fossilised tree resin, not a mineral: soft, light and warm to the touch. Origin (Baltic), symbolism, AmetrineAmetrine is a quartz that is both violet (amethyst) and yellow-orange (citrine), almost entirely sourced from AmmoliteAmmolite is an iridescent gem taken from the fossil shell of Cretaceous ammonites, mined mainly in Alberta (CaAmethystAmethyst is the violet variety of quartz, ranging from lilac to deep purple. Origin of the name, history, symbAndalusite (chiastolite)Andalusite is an aluminium silicate. Its chiastolite variety shows a dark cross in its cross-section, caused bAngel auraAngel aura is rock crystal coated under vacuum with a fine metallic layer that gives it a pearly, iridescent vAngeliteAngelite is the trade name of a blue-grey anhydrite from Peru, very soft and sensitive to water. Origin, tradiApatiteApatite is a calcium phosphate with a hardness of 5, found in blue, green or yellow. Origin of the name, tradiApophylliteApophyllite is a soft mineral that forms small transparent pyramid-shaped crystals inside cavities in volcanicAqua auraAqua aura is transparent rock crystal coated with a fine layer of gold deposited under vacuum: a brilliant turAragoniteAragonite is a calcium carbonate related to calcite, named after Aragón in Spain. Discover its appearance, traAstrophylliteAstrophyllite is a rare silicate with golden star-shaped blades, often set in white feldspar. It is soft and fAuralite 23Auralite 23 is a trade name for a Canadian amethyst rich in inclusions of many minerals. Here is what is estabBlue AventurineBlue aventurine is most often a quartz coloured by dumortierite. Its real nature, traditional symbolism, care,Red aventurineRed aventurine is a red to orange-brown quartzite, speckled with flakes of iron (haematite, goethite). Nature,Green AventurineGreen aventurine is a glittering quartz coloured by tiny flakes of fuchsite. Origin, traditional symbolism, caAzuriteAzurite is a deep blue copper carbonate, once a source of pigment. Origin, traditional symbolism, care precautAzurite-malachiteAzurite-malachite combines two copper carbonates, one dark blue and one green. A soft and sensitive stone, it
B
BismuthBismuth is a silvery-grey metal. The iridescent stepped crystals sold as stones are made by melting, so they dBixbiteBixbite, or red beryl, is a variety of beryl in a deep red, coloured by manganese. Extremely rare, it comes alPetrified WoodPetrified wood is fossilized wood turned into stone, most often as quartz or chalcedony. Formation, famous forBornite (peacock stone)Bornite is a copper ore whose surface tarnishes into blue, violet and red. Many "peacock stones" sold are chalBronziteBronzite is a brown pyroxene with a bronze sheen, close to enstatite. Mineral nature, traditional symbolism, cBerylBeryl is a beryllium silicate whose family includes emerald, aquamarine, morganite and heliodor. Varieties, hi
C
White CalciteWhite calcite is a soft calcium carbonate (hardness 3), creamy white and translucent. It is the mineral of limBlue CalciteBlue calcite is a soft calcite in pale shades of blue. Its nature, the origin of its colour, its symbolism of Yellow CalciteYellow calcite, also called honey calcite, is a calcite coloured by iron oxides. Soft (hardness 3) and transluOptical CalciteOptical calcite is a clear, colourless calcite that splits the images seen through it in two. Also called IcelOrange CalciteOrange calcite, also called honey calcite, is a soft calcium carbonate in amber tones. Its nature, traditionalPink CalcitePink calcite is a calcite tinted pink by manganese or, more rarely, cobalt. Soft (hardness 3), it is told aparRed CalciteRed calcite is a calcite coloured brick red or orange by iron. Soft (hardness 3), it should not be confused wiGreen CalciteGreen calcite is a soft calcite in gentle shades of green. Its nature, the origin of its colour, traditional sChalcedonyChalcedony is a microcrystalline silica that gives rise to agate, carnelian and chrysoprase. Nature, history, CarborundumCarborundum is silicon carbide made in a factory. Its grey chips with rainbow reflections sold as stones are aCavansiteCavansite is a hydrated calcium and vanadium silicate of intense sky blue that forms small radiating balls. RaChalcopyriteChalcopyrite is a brassy yellow copper and iron sulfide, often iridescent, and the main copper ore. Its natureCharoiteCharoite is a violet, marbled silicate from Siberia, only formally described in 1978. Its nature, origin, tradChrysoberylChrysoberyl is a beryllium aluminium oxide (BeAl2O4), hard (8.5), that is not a beryl. Its best-known varietieChrysocollaChrysocolla is a soft, blue-green copper silicate, often mixed with quartz. Its nature, the history of its namChrysopraseChrysoprase is an apple-green chalcedony, coloured by nickel. Its hue recalls jade, and tradition links it to CinnabarCinnabar is a bright red mercury sulphide (HgS), the historical source of vermilion. Very beautiful but toxic:CitrineCitrine is a yellow to orange quartz with a hardness of 7. Rare in its natural state, it is often amethyst thaCoralPrecious coral is the limestone skeleton of a marine animal (Corallium rubrum in the Mediterranean). An ancienCarnelianCarnelian is an orange to reddish-brown chalcedony, coloured by iron oxides. Used since Antiquity for seals, iRock crystalRock crystal is colourless, transparent quartz with a hardness of 7. A symbol of clarity in many traditions, iCopperCopper is a reddish metal, one of the first used by humanity. It is sometimes found in its native state, as brCupriteCuprite is a dark red copper oxide with brilliant crystals. Soft and sensitive to acids, it is mainly kept as KyaniteKyanite (also called disthene) is a blue aluminium silicate in bladed crystals, with a surprising hardness: soCelestiteCelestite, also called celestine, is a sky-blue strontium sulfate that forms crystal geodes. Its nature, deposCerussiteCerussite is a white to grey lead carbonate with an adamantine lustre, often twinned into star shapes. It cont
D
DanburiteDanburite is a colourless to white calcium borosilicate with a hardness of 7 to 7.5, first described in 1839 nDiamondDiamond is carbon crystallised deep underground, the hardest natural material yet also brittle. Formation, hisHerkimer DiamondThe Herkimer 'diamond' is not a diamond: it is a clear double-pointed quartz crystal that formed in the dolostDiopsideDiopside is a calcium magnesium silicate. Its green variety, chrome diopside, is coloured by chromium; a blackDioptaseDioptase is an emerald-green copper silicate, rare and fragile, long mistaken for emerald. It is associated wiDolomiteDolomite is a calcium magnesium carbonate, soft and white, pink or grey. It gave its name to the Dolomites, thDumortieriteDumortierite is a blue aluminium borosilicate, described near Lyon at the end of the 19th century. Hard and op
E
EuclaseEuclase is a blue, pale green or colourless beryllium aluminium silicate, hard (7.5) but very fragile because EudialyteEudialyte is a rare silicate ranging from pink to raspberry red, described in 1818 in Greenland. Soft, soluble
F
FluoriteFluorite is a highly coloured calcium fluoride with a hardness of 4 and perfect cleavage. It gave its name to FuchsiteFuchsite is a green mica coloured by chromium, very soft and sparkling. It is mostly found in green aventurineFulguriteFulgurite forms when lightning strikes the ground and melts sand or rock into a glass tube. Very fragile, it i
G
GalenaGalena is a grey, shiny, very heavy lead sulphide that forms cubes. An ore of lead and silver, it contains leaGoethiteGoethite is an iron oxyhydroxide, brown to black, that makes up much of rust and ochres. It is named after theGoldstoneGoldstone is not a natural stone but a manufactured glass, speckled with copper crystals. Born in Venice, it iGarnetGarnet is a family of silicates, most often a deep red, with a hardness of 6.5 to 7.5. It is associated with vAlmandine garnetAlmandine is the most common dark red garnet: an iron-aluminium silicate, hard (7 to 7.5), known since antiquiSpessartine garnetSpessartine is an orange to reddish-orange garnet rich in manganese. Its most vivid variety, known as “mandariTsavorite garnetTsavorite is a vivid green grossular garnet, coloured by vanadium or chromium. Discovered in Tanzania in 1967,GypsumGypsum is a hydrated calcium sulphate, the softest mineral on the Mohs scale after talc. Depending on its form
H
HackmaniteHackmanite is a variety of sodalite that turns pink or takes on colour in the sun, then fades in the dark. DisHessoniteHessonite is an orange to honey-brown grossular garnet, known as the “cinnamon stone”. It is famous in Sri LanHiddeniteHiddenite is the emerald-green variety of spodumene, coloured by chromium. Discovered in North Carolina aroundHowliteHowlite is a white borate veined with grey, soft and porous. Very often dyed blue to imitate turquoise: here iHeliodorHeliodor is a golden yellow to yellowish-green beryl whose name means “gift of the sun”. Hard (7.5 to 8), it oBloodstoneBloodstone, or heliotrope, is a dark green chalcedony speckled with red. An ancient stone, long engraved into HematiteHematite is a very dense iron oxide, steel grey with a metallic shine, whose powder is blood red. A traditionaRainbow hematite“Rainbow hematite” refers to iridescent hematite. A rare natural iridescent hematite exists (Brazil), but manyHemimorphiteHemimorphite is a zinc silicate, often a pastel blue to green, forming rounded crusts. An ancient zinc ore tha
I
IdocraseIdocrase, or vesuvianite, is a green to brown calcium silicate first described from Vesuvius. Its green varietIndigoliteIndigolite, or indicolite, is blue tourmaline: a variety of elbaite, hard (7 to 7.5), dichroic and pyroelectriIoliteIolite is the gem variety of cordierite, blue-violet, which changes colour depending on the viewing angle. A pVegetable ivory (tagua)Vegetable ivory, or tagua, is the hard white seed of a South American palm (Phytelephas). A durable plant mate
J
Jade“Jade” in fact covers two minerals, nephrite and jadeite, both exceptionally tough. A major stone of ancient CJetJet is a black, light lignite, brilliant when polished, formed from fossilised wood. A stone of Victorian mourK2 jasper“K2 jasper” is not a jasper: it is a white granite speckled with small spheres of blue azurite, from northern Cappuccino jasperCappuccino jasper is a cream-brown stone with dark veins, sold as jasper. Its nature varies depending on the sDalmatian jasper'Dalmatian jasper' is a cream-white rock spotted with black, from Mexico. Despite its name, it is not a jasperYellow jasperYellow jasper is an opaque quartz with microscopic grains, coloured yellow by iron oxides. Affordable and sturKambaba jasperKambaba jasper is a dark green rock with black circles from Madagascar, often presented as a 3-billion-year-olLeopard jasperLeopard jasper is a stone with round spots that evoke a big cat's coat, sold as jasper but most often a MexicaOchre jasperOchre jasper is a yellow-brown jasper, coloured by hydrated iron oxides. Trade name, origin of the ochre, cautOcean jasperOcean jasper is a rock from Madagascar covered in small coloured spheres. A trade name for a spherulitic chalcOrbicular jasperOrbicular jasper is a stone from Madagascar with small concentric spheres, also sold as ocean jasper. ChalcedoPicture jasperPicture jasper shows bands and patterns that suggest horizons, hills or rivers. A stone with designs that are Polychrome Jasper“Polychrome jasper” is a trade name for multicoloured jaspers, most often from Madagascar: an opaque, hard micRhyolite jasper'Rhyolite jasper' is a silicified volcanic rock, often coloured and spotted, sold under various names such as Red jasperRed jasper is an opaque microcrystalline quartz coloured by iron. One of humanity's oldest stones, it is tradiBloodstoneBloodstone (French: jaspe sanguin), also called heliotrope, is a dark green chalcedony with red spots of hematZebra jasper"Zebra jasper" is a trade name for stones striped in black, white and brown. Depending on the batch, it is jas
K
KunziteKunzite is the pink-lilac variety of spodumene, a gem described in 1902 and named after the gemmologist GeorgeBlack kyaniteBlack kyanite is kyanite coloured by graphite, most often sold in fan-shaped clusters of blades. What it is, hOrange kyaniteOrange kyanite is a rare variety of kyanite, coloured by manganese and found mainly at Loliondo (Tanzania). NaGreen kyaniteGreen kyanite is a kyanite in shades of green, from yellowish green to bluish green. Origin of the colour, fra
L
LabradoriteLabradorite is a dark grey feldspar whose blue, green or golden flashes appear when you tilt it. Origin, symboLapis lazuliLapis lazuli is a deep blue rock flecked with golden pyrite, used for some 7,000 years in jewellery and as theLarimarLarimar is a blue variety of pectolite mined in the Dominican Republic, with the tones of clear water. Origin,Apache TearThe Apache tear is a small nodule of black obsidian, a core of volcanic glass preserved in perlite. It is alsoLarvikiteLarvikite is a grey Norwegian rock with bluish flashes, formed nearly 300 million years ago. Origin, traditionBlue LarvikiteBlue larvikite is a rock from Norway (monzonite) whose feldspar crystals reflect a silvery blue sheen. It is nLazuliteLazulite is a blue magnesium aluminium phosphate. It is neither lapis lazuli nor lazurite: mineralogy, depositLepidocrociteLepidocrocite is a red-brown iron oxyhydroxide, a cousin of goethite. It is mostly seen as a red inclusion in LepidoliteLepidolite is a lithium-rich mica in pink to violet, made of fine shining flakes. Origin, the history of its n
M
MagnesiteMagnesite is a white to grey magnesium carbonate, soft and porous, very often dyed blue to imitate turquoise. MagnetiteMagnetite is a black iron oxide, the most magnetic natural mineral. Its magnetised variety, lodestone, gave itMalachiteMalachite is a vivid green copper carbonate with concentric bands, used as a pigment and ornamental stone sincMangano-calciteMangano-calcite is a pink calcite coloured by manganese. Gentle in tone and soft in hardness, it is worked intMarcasiteMarcasite is an unstable iron sulphide, a cousin of pyrite. So-called marcasite jewellery is in fact made of pMoldaviteMoldavite is a natural green glass formed about 15 million years ago by an asteroid impact in Germany. Origin,MolybdeniteMolybdenite is a very soft, silvery grey molybdenum sulphide that stains the fingers. Mineralogy, industrial uMookaiteMookaite is a jasper from Western Australia in cream, rust, pink and yellow tones, formed from the silica of tMorganiteMorganite is a peach-pink to salmon-pink beryl, from the same mineral family as emerald and aquamarine. OriginMuscoviteMuscovite is white mica, a silicate in soft, shiny sheets. Very soft, it was once used as window glass in RussMeteoriteA meteorite is a fragment of an asteroid, of Mars or of the Moon that has fallen to Earth. Stony, iron or mixe
N
Mother-of-PearlMother-of-pearl is the iridescent inner layer of shells, made of aragonite and a protein. An animal-derived maNuummiteNuummite is a black rock from Greenland, almost three billion years old, showing copper, gold and blue-green f
O
Mahogany obsidianMahogany obsidian is a black volcanic glass marbled with brown-red by iron oxides. Origin of its colour, symboSilver ObsidianSilver obsidian is a black volcanic glass whose silvery reflections appear in the light. Its shimmer comes froGolden ObsidianGolden obsidian is a black or dark brown volcanic glass that shows golden reflections depending on the angle. Snowflake obsidianSnowflake obsidian is a black volcanic glass speckled with white or grey snowflake-shaped patches, caused by tMentogochol Obsidian“Mentogochol” is a trade name found among stone dealers in Mexico, presented as an obsidian. No mineralogical Black obsidianBlack obsidian is a shiny volcanic glass, used since prehistory to make tools and mirrors. Origin, symbolism, Celestial eye obsidianCelestial eye obsidian is a trade name for black obsidian with light patterns suggesting an eye. What can be sOnyxOnyx is a chalcedony striped with parallel black and white bands. The word is also wrongly used for calcite stOpalOpal is hydrated silica with no crystalline structure, famous for its play of colours. The October birthstone,Blue opalBlue opal is most often a common opal from Peru, a milky blue-green. Many pieces sold under this name are in fMadagascan Opal“Madagascan opal” most often refers to common opal with no play of colour, dark or green, sold as spheres. It Pink opalPink opal is a common opal, without play of colour, in a soft, milky pink. It comes mainly from Peru and is alOpalineOpaline is not a stone: it is a milky glass, first a 19th-century tableware art, then the bluish “opalite” sol
P
PearlA pearl is an organic gem formed by a mollusc in layers of nacre. Natural pearls are very rare; almost all peaPhenakitePhenakite is a very hard, very brilliant beryllium silicate, often colourless, long mistaken for quartz. A rarPicasso Jasper'Picasso jasper' (or Picasso stone) is, according to the sources, a marble or a dolomite veined with iron or gArizona Stone'Arizona stone' is a trade name tied to an origin, with no fixed definition. Here are the materials it may covLava stoneLava stone is a porous, lightweight, dark volcanic rock. Very popular as diffuser bracelets, it is cared for dMoonstoneMoonstone is a feldspar with a milky, shifting sheen called adularescence. It is fragile and often confused wiBlack moonstone“Black moonstone” is not a specific species: in shops the name covers dark feldspars with a sheen, but also otSunstoneSunstone is a feldspar with copper or golden sparkles. It should not be confused with goldstone, a manufactureFairy stone“Fairy stone” most often refers to staurolite, whose twinned crystals form a cross, and also evokes legendary PietersitePietersite is a chatoyant quartz breccia with swirling golden and blue reflections. Discovered in Namibia, it PrasiolitePrasiolite is a pale green quartz, almost always obtained by heating amethyst. Hard and luminous, it is sometiPrehnitePrehnite is a pale green silicate in rounded clusters, named after Colonel von Prehn. Pretty, gentle and afforPyritePyrite is a golden iron sulphide, often with cubic crystals. Nicknamed “fool’s gold”, it is attractive but tarPyromorphitePyromorphite is a lead phosphate in green, yellow or brown, forming barrel-shaped crystals. A heavy, toxic colPeridotPeridot is the gem variety of olivine, in colours from olive green to bright yellow-green. The August birthstoPetalitePetalite is a colourless or pale lithium aluminium silicate, discovered in Sweden in 1800. It is the mineral i
Q
Aura quartzAura quartz is a quartz crystal coated in a laboratory with a thin, iridescent layer of metal. It is not a natBlue quartz“Blue quartz” covers several materials: natural quartz coloured by inclusions, quartz treated on its surface (Cathedral quartzCathedral quartz is not a separate variety but a shape: a quartz crystal with multiple points or stepped facesLemon quartzLemon quartz is a pale yellow to yellow-green quartz. Most often it is colourless or smoky quartz that has beeGolden quartz“Golden quartz” is a trade name for a yellow, honey-gold quartz. It may be natural, heated or irradiated: the Phantom quartzPhantom quartz contains, inside the crystal, the ghostly outline of an earlier point. This “silhouette” is a gStrawberry quartzStrawberry quartz is a pink to red quartz speckled with tiny reddish inclusions (iron oxides). Much of the “stSmoky quartzSmoky quartz is a brown to black quartz whose tint comes from natural irradiation. Cairngorm in Scotland, moriHematoid quartzHematoid quartz is quartz coloured red or orange by hematite inclusions. Hard and often mottled, it is easy toGarden quartz (lodolite)Garden quartz, or lodolite, is a rock crystal containing chlorite and other mineral inclusions that form landsMilky quartzMilky quartz is a white quartz, translucent to opaque, whose milky look comes from tiny bubbles of liquid and Snow quartzSnow quartz is a trade name for opaque white quartz, most often milky quartz. Hard (7), snow-white, it comes fRose quartzRose quartz is a pale pink variety of quartz (silica), often milky. In tradition it is associated with tendernRed quartz“Red quartz” is a trade name for quartz coloured by iron inclusions (fire quartz, hematoid quartz), dyed or crRutilated quartzRutilated quartz is quartz threaded with golden needles of rutile (titanium oxide), nicknamed “Cupid’s darts” Titanium quartzTitanium quartz is a quartz crystal coated under vacuum with a thin layer of titanium, which gives it rainbow Tourmalinated quartzTourmalinated quartz is clear quartz running through with black needles of tourmaline (schorl). Hardness 7: thGreen quartz“Green quartz” is a trade name covering prasiolite, quartz with green chlorite or mica inclusions, dyed or irr
R
RedstoneRedstone is a red-brown synthetic glass flecked with copper, a cousin of goldstone, invented in Venice. It is RhodochrositeRhodochrosite is a pink to red manganese carbonate, often banded with white: the “Inca Rose”, national stone oRhodoliteRhodolite is a pinkish-red to purple garnet, a mixture of pyrope and almandine. Its name, coined in 1898 in thRhodoniteRhodonite is a pink manganese silicate, veined with black by manganese oxides. Hardness 5.5 to 6.5, used in jeDesert RoseThe desert rose is a cluster of gypsum crystals (sometimes barite) formed in the desert, shaped like petals. VRubelliteRubellite is red to pink-red tourmaline, an elbaite coloured by manganese. Hard and vivid, it is sometimes misRubyRuby is the red variety of corundum, coloured by chromium. Very hard (9), it is one of the four precious gemstRuby-ZoisiteRuby-zoisite, also known as anyolite, is a green rock from Tanzania dotted with opaque red ruby crystals. Soft
S
SapphireSapphire is the variety of corundum in every colour except red, best known in blue. Hardness 9. Heating is comSardonyxSardonyx is a banded chalcedony alternating reddish-brown bands (sard) and white bands (onyx). A stone of sealScoleciteScolecite is a white zeolite in radiating needles, found in the basalts of India and Iceland. Fragile and sensSeptariaSeptaria (also called dragon stone) is a nodule of clay and limestone whose cracks are filled with yellow or bSerpentineSerpentine is a family of soft green minerals with a snakeskin-like pattern. A popular decorative stone that cShattuckiteShattuckite is a deep blue copper silicate, discovered in 1915 at Bisbee (Arizona). A soft stone that containsShiva lingamThe Shiva lingam is a pebble polished by the Narmada river (India), venerated in Hinduism as a symbol of ShivaShungiteShungite is a black rock very rich in carbon, about 2 billion years old, from Karelia (Russia). It is not a miSmithsoniteSmithsonite is a zinc carbonate in soft pastel shades (pink, blue-green, lavender), named in honour of the sciSodaliteSodalite is a deep blue mineral streaked with white, often mistaken for lapis lazuli. Its name refers to its sNative sulphurNative sulphur is a very soft, bright yellow mineral that crackles in the hand and burns with a blue flame, reSphaleriteSphalerite, or blende, is the main zinc ore. Brilliant, from yellow-brown to black, it is rare as a clear gem,SpinelSpinel is a hard gem that was long mistaken for ruby: several “rubies” in the British crown jewels are in factBlack spinelBlack spinel is a very hard magnesium aluminium oxide, coloured by iron, cut into cabochons or facets. A robusStauroliteStaurolite, or cross stone, is a brown silicate whose crystals naturally cross each other in the shape of a crStibniteStibnite is a grey metallic antimony sulphide that forms long, shiny blades. A collector's mineral, soft and tStromatoliteStromatolite is a layered fossil built by cyanobacteria hundreds of millions, even billions, of years ago. A wSoapstoneSoapstone, or steatite, is a soft rock made mainly of talc. It feels smooth to the touch and is easy to carve.SugiliteSugilite is a rare violet-to-pink silicate, discovered in Japan and famous for the fine material mined in SoutOregon SunstoneOregon sunstone is a labradorite-type feldspar filled with tiny copper particles. Red, green or bicoloured: OrSuper SevenSuper Seven is a Brazilian quartz (Espírito Santo) said to contain seven different minerals. An appealing tradSeleniteSelenite is the common name for gypsum in fine crystals or silky fibres, white and translucent. Very soft (harSeraphiniteSeraphinite is a trade name for a dark green clinochlore from Siberia, with silvery feather-like patterns. Ver
T
TanzaniteTanzanite is the blue-violet variety of zoisite, discovered in Tanzania in the 1960s. A recent gem, fragile anThuliteThulite is the pink variety of zoisite, coloured by manganese and discovered in Norway. Mineralogy, the historGolden Tiger's Eye'Golden tiger's eye' is a trade name for yellow-gold to brown tiger's eye, the classic form of this stone withTopazTopaz is a hard gem in a wide range of colours, from colourless to imperial orange. Blue topaz on the market iBlue TopazBlue topaz is a topaz whose colour, in almost every case, comes from irradiation and heat treatment. A hard, cBicolour tourmalineBicolour tourmaline is an elbaite in which a single crystal carries two colours, for example pink and green. TBlack TourmalineBlack tourmaline, or schorl, is the most common tourmaline: an opaque black silicate with striated crystals. TWatermelon TourmalineWatermelon tourmaline is a two-coloured elbaite: a pink core surrounded by a green rim, like a slice of watermPink TourmalinePink tourmaline, often called rubellite when it tends towards red, is a transparent elbaite with delicate pinkGreen TourmalineGreen tourmaline, also called verdelite, is a green variety of elbaite that ranges from apple green to forest TugtupiteTugtupite is a rare mineral from Greenland, pink to crimson, which can change shade in light. It contains beryTurquoiseTurquoise is a hydrated copper-aluminium phosphate in colours from sky blue to blue-green. It has been prized Arizona TurquoiseArizona turquoise refers to turquoise mined in this American state (Sleeping Beauty, Kingman, Bisbee...), know
U
UlexiteUlexite, or TV stone, is a white borate whose fibres carry light: placed on a text, it projects the image ontoUnakiteUnakite is an epidotised granite mixing olive-green epidote, pink feldspar and quartz. It is a rock, not a sin
V
VarisciteVariscite is a soft green aluminium phosphate often confused with turquoise. It was already worked in Europe dVerditeVerdite is a green rock from southern Africa, made mainly of fuchsite (a chromium-bearing mica). It is also so
W
WavelliteWavellite is a green aluminium phosphate that forms small fibrous star-shaped suns. A rare, soft stone, first WulfeniteWulfenite is a lead molybdate forming orange to red platelets, highly prized by collectors. Fragile and toxic,
Z
ZinciteZincite is a red-orange zinc oxide, rare in nature. Most faceted stones on the market are synthetic, produced ZirconZircon is a highly brilliant zirconium silicate in a range of colours, not to be confused with cubic zirconia.ZoisiteZoisite is a calcium-aluminium silicate that includes tanzanite, pink thulite and the rock ruby-zoisite (anyol
É
EmeraldEmerald is the green variety of beryl, coloured by chromium or vanadium. A precious gem since antiquity, it isEpidoteEpidote is an olive to dark green silicate, described by Haüy in 1801. Its Greek name suggests growth; in trad
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St Lucy’s EyeSt Lucy’s eye is not a stone: it is the calcareous operculum, a sort of small lid, of a sea snail. It has longCat’s EyeIn gemmology, “cat’s eye” refers to the chatoyancy effect, a moving band of light, and above all to chrysoberyHawk's eyeHawk's eye is a blue-grey fibrous quartz with a silky sheen, the blue cousin of tiger's eye. Very bright bluesIron Tiger’s Eye“Œil de fer” corresponds to Australian tiger iron: a banded iron formation mixing tiger’s eye, hematite and reBull's eyeBull's eye is a heated tiger's eye that takes on a deep red-brown. It is an old, common treatment that is wortTiger's eyeTiger's eye is a golden brown fibrous quartz with a silky sheen. A stone of courage in tradition, it is sturdyBlue Tiger's EyeBlue tiger's eye refers either to natural blue-grey hawk's eye or, sometimes, to dyed stones. Nature, crocidolRed Tiger's EyeRed tiger's eye is most often golden tiger's eye that has been heated, which turns its iron red. Also called b
The meanings mentioned belong to tradition and symbolism. They are neither promises of results nor medical advice.