s
Russian Gemstones Encyclopedia

Vladimir Bukanov. Russian Gemstones Encyclopedia

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

VESUVIANITE


VESUVIANITE (Vesuvian—Vésuvianite—¬езувиан) (Werner, A.G. 1795 in Klaproth, M.N., 1795), after its discovery location in ejected volcanic blocks at the Vesuvius Mt., Campagna, Italy.

Composition & Properties. Silicate – Ca19Al10(Mg,Fe)3[(OH,F)10|(SiO4)10|(Si2O7)4], subclass diorthosilicates, tetragonal system. Hardness 6.5. Density 3.3-3.4. Glass luster. Fragile. Vesuvianite is found in the shape of columnar, bypyramidal and flattened crystals of a square section. Transparent to translucent. Color: from red to violet, rarely light blue or colorless. The character of coloring can be zonal, polychromatic and spotty. They classify following varieties of: viluite – with the content of admixture of B2O3 more than 1%, sometimes, it is described as a separate mineral; xanthite – yellowish-brown, laurelite – greenish-golden, heteromerit – oily-green, titanvesuvianite – reddish-brownish to rose with admixture of TiO2, chrome-vesuvianite – emerald-green with admixture of chromium, cyprine or copper vesuvianite – sky-blue or greenish-blue with admixture of CuO up to 1%; manganvesuvianite, and egeran – reddish-brownish, often radial-rayed. As an ornamental stone, cryptocrystalline green variety is well-known – vesuvianite rock. In mixture with grossular garnet it has the trade name vesuvianite jade, and in the U.S.A. – californite, or American jade.

Deposits. Vesuvianite is a typical contact-metasomatic mineral characteristic for calcareous skarns. In Russia, in the Polar Urals, ornamental apple-green vesuvianite rock was extracted at the Nyrdvomenshor deposit of nephrite, in the massif Ray Iz. In the Subpolar Urals Mts., was discovered also at the Vangyr deposit. In the Middle Urals, they discovered crystals of vesuvianite at the Bazhenovskoye deposit, near Asbest. Near Verkhne-Neyvinsk, in the Kazanka River, and at the Kluchevskoy mine, near Yekaterinburg they found chrome-vesuvianite. In the South Urals, in chlorite schists of the Nyazemskie and Shishimskie Mts., near Zlatoust, they discovered crystals of vesuvianite available for faceting. At the Shishimskie mines, ornamental apple-green vesuvianite rock and garnet-vesuvianite rock were discovered. This rock is yellow-green to olive-green, sometimes with spotty pattern; it is well polished. In East Siberia, crystals of vesuvianite were found in Khakassia, at the Yuliya mine. In trappen rocks of Yakutia, on the Vilyui River basin, crystals of viluite length reached 5 cm. In the north of Yakutia, in the basin of the Selennyakh River, at the Munlikan deposit, they discovered vesuvianite jade. In the Magadan Region, crystals of vesuvianite were discovered at the Kanyon deposit, near Seimchan.

In Kyrgyzstan, in the Chatkalskiy Ridge, they registered findings of light blue cyprine. In Kazakhstan, massive vesuvianite was discovered at the Ak Chagyl deposit. In Azerbaijan, at the Kedabek deposit, near Dashkesan, they find crystals of vesuvianite up to 8 cm. long. In Sweden, in the region of Gökume, they extract crystals of green manganous-containing vesuvianite – gökumite or loboit. In Norway, blue-green cyprine occur at the deposits Souland and Telemark Smith; also olive green crystals up to 5x4 cm. at Kristiansand, Vest-Agder, and Eiker, near Oslo, were found. In Finland, at the Frugård deposit, they extracted vesuvianite under the local name frugårdite. In the west of Czech Rep., near Cheb, there are deposits of gem-quality vesuvianite in famous radial columnar aggregates of brown egeran. In Romania, in skarns near Ciklowa Montan˘ a, they found brown to yellowish bipyramidal crystals of vesuvianite up to 6 cm. In Italy, its variety heteromerit at first occur in the Vesuvius, at the deposits Monte Somma and Monzoni, near Predazzo. Bright green and brownish crystals of vesuvianite at the Valle d’Ala deposit, Piedmont, was extract. Similar crystals are found in alpine veins of Switzerland, near Zermatt, Valais canton; and also in Austria, near Tyrol.

In Morocco, brown crystals vesuvianite – duparcite and rose titanvesuvianite at the Azemmour (Azzegour) deposit, Atlas Mts., and crystals up to 6x4 cm. at Imilchil, Midlet region, were fund. From deposits of Tanzania gem-quality brown cyprine comes to the market; from Kenya – yellow-green and brown vesuvianite; and in Mali, at a deposit to the south from Sandare they found crystals of vesuvianite 15 cm. In Namibia, brown red crystals up to 2 cm. at the Vis deposit were found. In South Africa, purple to lilac vesuvianite occurs at the N’Chwaning mine, Northern Cape Prov. On Sri Lanka, golden-brown crystals of vesuvianite from placers was extract. In Pakistan, more significant deposits of vesuvianite are known, in the Baluchistan Prov., where beside faceting material also massive ornamental material comes from.

In North America, deposits of vesuvianite are known in Canada, in the Québec Prov. At the Jeffrey mine, near Asbestos, yellow, brown, green, and pink-lilac polychromatic vesuvianites up to 18 cm. are extract. At the Laurel deposit, they find yellow grained masses and greenish-golden crystals of laurelite; and in the Laurentian Mts., they discovered placers with golden-brown crystals of xanthite. In the U.S.A., bright green and brownish crystal vesuvianite up to 30 cm. occur at the Magnet Cove deposit, Arkansas; in New Jersey, – sky-blue cyprine at the Franklin deposit, Sussex Co.; in the New York State, – brown xanthite at the Amity deposit, Orange Co., also crystals of vesuvianite up to 15 cm. at the deposit near Olmstedville, Essex Co. In California, massive translucent californite from yellow-green to dark green color were extracted at the deposits Crestmore, Riverside Co., at Pulga, Butte Co., and Indian Creek, Siskiyou Co., also crystals of green viluite at the Bill Valley mine, Tulare Co.

Synonyms. Glassy agate | Cholophanite, from Gk. “chalos” – beautiful and “phone” – sound, because of the melodically sound of fine plates | Chrome-idocrase | ~ chrysolite: commercial ~, Italian ~, Vesuvian ~, volcanic | Cupreous idocrase | Cyprine (ciprine), from Gk. “cypros” – cuper, after the content | Dikarkit, obs. | Duparcite, after the Switzerland researcher L. Duparc | Egeran, after the discovery location near Cheb (Eger), Czech Rep. | Vilyuian emerald | Evreinovite (jevreinoffite, jevreinovite), after the Russ. chemist P.I. Evreinov | Pyramidal garnet | Gahnite, mist. | Genevite, after the discovery location near Geneva, Switzerland | Heteromerit, from Gk. “heteros” – another and “meros” – a part | Heteromesite, obs. | Hyacinth, obs. | False hyacinth | Vesuvian hyacinth | Hyacinthine, obs. | Idocrase, from Gk. “idos” – shape and “crasis” – mixed one, because crystals are resembling other minerals, discr. | Loboit, after the Swedish researcher Lobo da Silveira | Manganidocrase | Plasma | Volcanic schorl | Viluite (wilouite), after the discovery location on the Vilui River, Yakutia, Russia | Xanthite, from Gk. “xantos” – yellow, after the color.

Ornamental rocks. ~ jade: Californian ~, matrix ~, Pakistan ~, Vesuvianite ~ | American nephrite | Californian nephrite.

Cut Gems. Transparent crystals of vesuvianite are faceted. The biggest stones up to 15 ct. were made from rough material from the Pulga deposit in California, the U.S.A.; and from Kenyan and Italian rough material they made faceted stones up to 10 ct. In the Smiths. Inst., Wash. there a faceted brown vesuvianite from Italy, 3.5 ct.; and in the Museum of Calgary, Canada, there is a brown stone from Kenya 8.5 ct. Massive varieties are cut in cabochons and used in stone-carving.

Similarity. It looks like demantoid, diopside, epidote, hyacinth, olivine, and sinhalite.

Search