1Z77 



ZINC. 



ZINGIBERACEyE. 



1278 



Some varieties contain small portions of iron and cadmium. 

 Oxysulphuret of Zinc; Voltzite. It occurs in the form of small hemi- 

 spheres, which are divisible into thin layers. Fracture conchoidal, 

 irregular. Hardness 4'5. Colour yellowish-red, interspersed with 

 brown bands. Lustre pearly on the natural layers, but vitreous or 

 resinous in the other directions. Slightly translucent, opaque. Specific 

 gravity 3'66. It occurs in Cornwall (?), and at Roziers, department of 

 Puy-de-Ddme, France. Analysis by M. Fournet : 



Sulphuret of Zinc 81-0 



Oxide of Zinc 15-0 



Oxide of Iron 1*8 



Organic Matter 2-2 



100 



Carbonate of Zinc ; Calamine. It occurs crystallised and massive. 

 Its primary form is a rhomboid. Cleavage parallel to the primary 

 planes. Fracture uneven, conchoidal. Hardness: scratches fluor- 

 spar, but is scratched by apatite. Colour white, yellowish-white, 

 gray, brown, and green. Streak white. Lustre vitreous. Translu- 

 cent. Opaque. Specific gravity 4 '4 4 2. Massive varieties amorphous ; 

 structure granular, compact, reniform, botryoidal, stalactitic; fibrous. 

 This ore occurs rather abundantly, and is found both in veins and beds 

 in various parts of England, France, and in America. Analysis by 

 Smithson, (1) from Somersetshire, (2) from Derbyshire : 



(1) (2) 



Carbonic Acid .... 35-2 34-8 



Oxide of Zino .... 64-8 65-2 



100 100 



Soluble, with the extrication of carbonic acid gas, in acids. 

 Hydrous Carbonate of Zinc ; Hydrout Calamine. It occurs usually 

 massive or incrusting other minerals. Texture fine-grained and close. 

 Hardness 2 to 2-5. Colour white or grayish or yellowish- white. Dull ; 

 opaque. Specific gravity 3-584 to 3-598. It frequently accompanies 

 the preceding species. It is soluble in acids with the extrication of 

 carbonic acid gas. It contains : 



Carbonic Acid 13-52 



Oxide of Zinc 69-36 



Water 15-10 



97-98 



Sulphate of Zinc; LUterite. It occurs crystallised and massive. 

 Primary form a right rhombic prism. Fracture conchoidal. Hard- 

 ness 2-0 to 2-5. Brittle. Colour white, sometimes inclining to peach- 

 blossom-red and violet-blue. Streak white. Transparent ; translu- 

 cent. Lustre vitreous. Specific gravity 2-036. Soluble in water. 

 Taste astringent, nauseous, and metallic. Massive varieties amorph- 

 ous; structure granular, compact, botryoidal, reniform, stalactitic, 

 fibrous; sometimes investing other bodies. Before the blow-pipe 

 froths, and covers the charcoal with white flocks. It is found at 

 Holywell in Flintshire, Fahlun in Sweden, at Rammelsberg in the 

 Harz, and Schemnitz in Hungary. 



Beudant's analysis of the substance from Schemnitz, gives- 

 Sulphuric Acid 29-8 



Oxide of Zinc 28'5 



Oxide of Manganese 07 



Oxide of Iron 0'4 



Water . . . , 40-8 



100-2 



Phosphate (?) of Zinc; Hopeile.It occurs crystallised. Primary 

 form a right rhombic prism. Cleavage parallel to the great diagonal, 

 distinct. Fracture uneven. Hardness, scratches gypsum, is scratched 

 by fluor-spar. Colour white, grayish-white. Streak white. Lustre 

 vitreous, pearly on the cleavage plane. Transparent ; translucent. 

 Specific gravity 2'46. Before the blow-pipe yields water, but no 

 carbonic acid ; becomes milk-white, and melts into a clear colourless 

 glass. Soluble without effervescence in nitric or hydrochloric acid, 

 and slowly in sulphuric acid. It has been found hitherto only in the 

 calamine-mines of Altenberg, near Aix-la-Chapelle. It consists of 

 oxide of zinc, a little cadmium, an earth, and much water, probably 

 combined with phosphoric acid. 



Silicate of Zinc; Willemite. It occurs crystallised and massive. 

 Primary form an obtuse rhomboid. Cleavage easy, in a direction 

 perpendicular to the axis. Transverse fracture conchoids). Hard- 

 ness, readily scratches glass and phosphate of lime ; is scratched by 

 the knife. Colour usually yellow, brownish, or reddish-yellow, some- 

 times white and transparent. Specific gravity 4'18. Before the blow- 

 pipe, the crystals partly lose their transparency ; with borax, a globule 

 is obtained, which is transparent, with a small nucleus of silica floating 

 in it. it is found at Moresnet, Aix-la-Chapelle, and contains 



Silica 72-33 



Oxide of Zinc 27-67 



Hydrous Silicate of Zinc; Smithtmite ; Ekctric Calamine. It 

 occurs cryrtallised in attached and globular and botryoidal aggrega- 

 tion, of crystals. Primary form a right rhombic prism. Cleavage 

 parallel to the lateral planes. Fracture conchoidal, uneven. Hard- 

 new, cratches fluor-spar, and is scratched by felspar. Brittle. Colour 

 white, blue, green, yellow, and brown. Streak white. It becomes 



electric by heat. Lustre vitreous. Transparent ; translucent. Specific 

 gravity 3'379. When heated in a glass-tube yields water, and becomes 

 nilk-white. When heated before the blow-pipe with borax, it dissolves 

 nto a colourless glass, which does not become milky on cooling. 

 When powdered and heated in hydrochloric acid, the oxide of zinc is 

 dissolved, and the silica gelatinises on cooling. It is found at Mat- 

 ,ock in Derbyshire, and other parts of England; in Scotland, Germany, 

 and many other parts of Europe. It contains 



Smilhson. Berthier. 



Silica 25-0 25-0 



Oxide of Zinc .... 68-3 66-0 



Water 4-4 9'0 



97-7 100 



Aluminate of Zinc; Automalite. [GAHNITE.] 



Oxide of Zinc and Oxide of Manganese ; Red Oxide of Zinc ; 

 'partalitc. It occurs in imbedded small nodules and massive. 

 Cleavage parallel to all the planes of a regular hexagonal prism. 

 Fracture conchoidal. Hardness 4 to 4-5, easily scratched by the 

 jnife. Brittle. Colour bright-red. Streak orange-yellow. Lustre 

 adamantine. Translucent. Specific gravity 5'4 to 5'5. Massive 

 varieties amorphous, structure crystalline, granular. Before the blow- 

 pipe infusible per se ; but with borax gives a yellow transparent 

 jlass. In nitric acid dissolves without effervescence. It is found 

 only in New Jersey, North America. It contains 



Oxide of Zinc 88 



Sesqui-Oxide of Manganese . . . .12 



100 



Sulphuret of Zinc and Iron ; Marmatite. This is a definite com- 

 pound of sulphuret of zinc and of sulphuret of iron ; its structure is 

 lamellar, and colour black ; indeed it appears to be black blende 

 united with sulphuret of iron. It is found at Marmato, province of 

 Popayan, South America. It contains silica, which is a mere accidental 

 admixture. 



Bi-Seleniuret of Zinc and Protosulphuret of Mercury ; Riolite. It 

 occurs massive. "Structure granular. Lustre metallic. Colour light- 

 ;ray. Opaque. Specific gravity 5'56. Before the blow-pipe burns 

 with a fine violet-coloured flame, and exhales a strong smell resembling 

 that of decayed cabbage. When heated in a retort, silenium, mercury, 

 and a little sulphur sublime, and there remains oxide of zinc, which 

 is readily dissolved by acids. It contains lime, which must be con- 

 sidered as an accidental impurity. 



Bi-Seleniuret of Zinc and Bi-Sulphuret of Mercury; Oulebrite. 

 It occurs massive. Fracture earthy. Dull. Colour dull-red. Specific 

 gravity 5 "66. It is found at Culebras, Mexico. 



Oxide of Zinc, Oxide of Iron, and Oxide of Manganese ; Tephroite. 

 It occurs massive. Compact. Cleavage perfect in several directions, 

 two of them meeting at right angles. Fracture uneven. Hardness 

 5 to 6. Lustre adamantine. Colour ash-gray, tarnishing black. Streak 

 paler. Specific gravity 4'10. Before the blow-pipe it forms a black 

 slag. It occurs with FramUmite and Spartalite at Sparta, United 

 States. 

 ZINC SPAR. [Zitrc.] 



ZI'NGIBER. [ZlNGIBEBACEJE.] 



ZINGIBERA'CE^E, Qingerworts, a natural order of Endogenous 

 Plants. The plants belonging to this order are herbaceous, possessing 

 a creeping and often jointed rhizoma. Their stem is formed of the 

 cohering bases of the leaves, and is never branched. The leaves are 

 simple and sheathing, the blade being often separated from the sheath 

 by a taper neck ; they have a single midrib, from which diverge at 

 an acute angle numerous simple crowded veins. The flowers are 

 arranged in a dense spike or raceme, or a sort of panicle, which is 

 either terminal or radical. The flowers are supplied with spathaceous 

 membranous bracts, which usually lie in pairs. The calyx is superior, 

 tubular, 3-lobed, short. The corolla is tubular, irregular, with six 

 segments in two whorls ; the outer whorl is 3-parted, nearly equal ; 

 the inner is also 3-parted, and represents three stamens, the inter- 

 mediate segment is larger than the rest, and called the labellum, and 

 is often 3-lobed; the lateral segment is sometimes nearly abortive. 

 The stamens are three, distinct, of which the two lateral are abortive, 

 and the intermediate one fertile ; this is placed opposite the labellum, 

 and arises from the base of the intermediate segment of the outer 

 series of the corolla; the filament is not petaloid, and often extends 

 itself beyond the anther in the shape of a lobed or entire appendage ; 

 the anther is 2-celled, and opens longitudinally, the lobes often em- 

 bracing the upper part of the style. The pollen is light, granular, 

 globose, and smooth. The ovary is 3-celled ; the ovules attached to 

 a placenta in the axis ; the style filiform, and the stigma dilated and 

 hollow. The fruit is usually a 3-celled capsule, and sometimes from 

 abortion 1-celled. The seeds are roundish or regularly angled, and 

 sometimes with an aril; the albumen flowery ; the embryo inclosed 

 within a peculiar membrane called Yitellus, and Membrane of the 

 Amnios by Brown. 



This order of plants has been mostly placed with Sfarantacece. It 

 was first constituted by Brown, who pointed out the difference be- 

 tween it and Marantacece. The distinguishing characters of Zingi- 

 beracece are first, the structure of the seed, in which a fleshy body is 

 interposed between the embryo and the albumen, entirely enveloping 



