WABANITE :

Variety of brown-red jasper

WALKLERA :

Synonym for saponite

WARDITE :

Mineral present as inclusions ( matrix ) in variscite ;

It is a un hydrated phosphate of aluminium

Etym. : after the American mineralogist Ward

NaA1₃[(PO₄)₂(OH)₅]. H₂O

Physical and optical properties :

Colours : colourless, white, greyish green to green, yellowish-green, bluish resembling turquoise

Transparency : opaque

Hardness : 4.5

Density : 2.5 to 2.8

R.I. : 1.590 – 1.599

Birefringence : 0.009

Cleavage : parfait

Uniaxial positive

System tetragonal

WATER AGATE :

English Synonym for anhydre .

WATERMELON-TOURMALINE :

Variety of tourmaline with a centre coloured red or pink encircled by a green part

WATER CHRYSOLITE :

Prohibited appellation for a moldavite .

WATER SAPPHIRE :

Prohibited Appellation for a cordierite .

WART AGATE :

Variety of carnelian

WASSERCHRYSOLITH :

German name for an obsidian ; Prohibited appellation

WASSERKIES :

German name for marcassite .

WATER OPAL :

English Synonym for hyalite ;

or transparent to translucent Mexican opal with play of colours ;

Prohibited appellation for a moonstone

WATER SAPPHIRE :

English term for a sapphire of only slight blue colour  ;

Prohibited appellation for ua cordierite

WATER STONE :

English term designating, or a moonstone, or hyalite, or anhydre ;

Old term sometimes used in China to designate a jade

WAX AGATE :

Chalcedony of yellow to red or yellowish colour

WAX OPAL :

Variety of yellow opal with a waxy aspect

WEISKYITE :

Designates an alteration of serpentine

WEISSERKIES :

German name for a marcassite

WEISSIGITE :

Variety of orthoclase

WERNERITE :

Synonym for scapolite ;

Prohibited appellation for a jade

WHITBY JET :

Jet from Whitby in England and considered as jet of superior quality at the time it was used in jewellery .

WHITE CLIFFS OPAL :

Opal from White Cliffs, 6O miles north of Wilcannia, New South Wales (Australia), having generally a milky white body colour .

WHITE EMERALD :

Prohibited appellation for a Beryl containing caesium

WHITE GARNET :
Synonym of Leuco-garnet.

Variety of translucent white grossular garnet having the appearance of jade.

WHITE SAPPHIRE :

Commercial Appellation for an artificial stone, imitation for a brilliant cut diamond ; generally it is a synthetic colourless spinel, or a synthetic colourless corundum

designates equally a natural colourless to bluish sapphire, equally called leuco-sapphire

WILLEMITE :

Etym. : dedicated to William of Holland, Grand Duke of Luxembourg, that started the exploitation of the mines at Moresnet

Zn₂(SiO₄)

Physical and optical properties :

Colours : colourless, white, orange, brilliant citron yellow, reddish, green, brown, more rarely

              blue, black

Transparency : transparent to translucent

Lustre : resinous

Hardness : 5 to 6

Density : 3.89 to 4.18

R.I. : 1.691 (-0.001) – 1.719 (+0.006)

Birefringence : 0.028 to 0.033

Uniaxial positive

System hexagonal

WILLIAMSITE :

Variety of serpentine of the sub-group of the antigorites serving to imitate jade ; synonym for chrysotile-asbestos (amiant) ; crystallises forming fibrous masses, of very fine fibres, elastic and resistant, easily separated from one another

Mg₆[(OH)₈. Si₄O₁₀]

Physical and optical properties :

Colours : apple green, green with octahedron inclusions of black chromite, yellowish green,

              oily green

Transparency : translucent to opaque

Lustre : silky

Hardness : 2.5 to 4

Density : 2.50 to 2.61

R.I. : 1.500 – 1.570

System monoclinic

WILSONITE :

Variety of violet-red scapolite or synonym of pinite

WILUITE :

Variety of brownish green to green grossular garnet

or variety of idocrase from near the Wilui river in Siberia, of greenish brown to greyish green colour, equally called Wiluite of Siberia

WINCHELLITE :

Synonym for limonite

WISERITE:

Synonym for anatase

WOLF’S EYE :

Popular name given to a moonstone.

WOOD OPAL :

Fossilised wood that is also opalised ( the molecules of the wood are here replaced by opal ), conserving the structure of the wood

WOLLASTONITE :

Mineral interesting for gemmology only in so far as constituent of an ornamental stone called falsely pink garnet

Ca3(Si₃O₉)

Physical and optical properties :

Colours : white, greyish, yellow, red-brown

Transparency : translucent to opaque

Lustre : vitreous or pearly

Hardness : 4.5 to 5

Density : 2.8 to 3

R.I. : 1.620 – 1.630

Birefringence : 0.010 – 0.015

Cleavage : parfait

System monoclinic

WOROBIEFFITE :

Beryl of deep pink colour, Etym. dedicated to the Russian mineralogist Worobieff

WURTZITE:

Black hexagonal Sphalerite ; ZnS

WYOMING JADE :

Variety of American nephrite