Hardnes=3.5, 4.5. 



MINER 



Spec. gravity=3.6, 





Oryetogno- rhomboid. 



'* 3.9. 



V """~ Y """"*' External Character!. Colours yellow, white, brown, 

 and black. Occurs massive, disseminated, with pyra- 

 midal impre^ions; also in granular distinct concretions ; 

 and crystallized. The following are some of its prin- 

 cipal crystallizations : 



1. Primitive rhomboid. 



a. Perfect, with straight or spherical convex lateral 

 face*. 



b. Truncated on the apices. 



c. Truncated on the terminal edges. 



d. Rounded off on the apices and edges. 

 When the truncating planes in the variety I.e. 



become so large that the original planes disap- 

 pear, there is formed 



2. A still flatter rhomboid. 



From th variety 1 . d. there arises 



3. The spherical lenticular form. 



From the rhomboid with curved faces there is 

 formed 



4. The saddle-shaped lens. 



We sometime* observe the primitive form arranged 

 in rows, so as to form an 



5. Equiangular six-sided prism, flatly acuminated 

 with three plane*, which are set on the alternate 

 lateral plane*. 



Crystals middle-sized, small, and very small. Seldom 

 singly superimposed, a* is the ease with the lens, most 

 generally Aggregated in druses. Plane* of the lens de- 

 licate drusy, but of all die other forms generally smooth ; 

 and the lustre varies from splendent, through shining to 

 glistening. Internally generally glistening, sometimes 

 inclining to shining, and even to splendent ; but the 

 black variety is only glimmering, and the lustre is 

 pearly. The imperfect foliated fracture is sometimes 

 conjoined with the splintery ; and this occurs principal- 

 ly in the greenish-grey varieties. Fragment* rhomboidal 

 in the foliated varieties, but rather Miarp-dged in the 

 compact. Generally translucent on the edges, also 

 translucent ; but the black varieties are opaque. The 

 pale varieties afford a white, the darker varieties a yel- 

 lowish-brown streak. It is not particularly brittle, and 

 i* easily frangible. 



Chemical Characlert.h blacken*, and becomes 

 magnetic before the blowpipe, but does not melt : it ef- 

 ices with muriatic acid. It dissolves with ebulli- 

 tion in glass of borax, and communicates to it an olive- 

 green colour. Sttinheim. 



Cotulit*el Parti. Oxide of iron 75 



Carbonic acid 34.00 



Oside of manganese 0.75 

 Magnesia . 0.25 



I.-- . . 1.25100.00 



Kltproth, in Magaz. Naif. Fr. b. v. s. S35. 



(irngitoitic Situation. It occurs in veins in granite, 

 gneiss, mica-slate, clay- slate, and grey-wacke, and in 

 these it i* associated with ore* of lead, cobalt, silver, 

 and seldomer with nickel and bismuth ; more frequent- 

 ly with galena, grey copper ore, iron-pyrites, and grey 

 antimony ore. In other vein-, it is accompanied with 

 brown, red, and black iron ore, calcareous spar, and 

 quart/. But the most extensive formations of this mi- 

 neral are in limestone, by some referred to primitive, 

 l>y other* to secondary rocks, in which it is arranged 

 in thick beds. It also occurs filling up amygdaloidal 

 cavities in trap rocks. 



A L G Y. 499 



Geographic Situation. Europe. It occurs in small Oryctogno- 

 quantities in different places in England, Scotland, and ^^^ 

 Ireland ; but very abundant in Hessia, Carinthia, and 

 other countries on the continent of Europe. 



Uses. It affords an iron which is excellently suited 

 for steel making. The black variety is said to afford 

 the best kind of iron. 



GtNusIII. CALAMINE*. 

 Zink-Baryt, Mohs. 



One and three axes. Cleavage di-prismatic ; rhom- CALAHIXE. 

 boidal. If rhomboidal, = 4.2 and more. Hardness = 

 5.0 sp. gr. = 3.3, 4.5. 



This genus contains two species, viz. 1. Prismatic 

 Calami ne j and, 2. Rhomboidal Calamine. 



1. PRISMATIC CALAMIXK, or ELECTRIC CALAMINE, Prismatic 



Jameton Prismatischer Zink-Baryt, Mohs. Zinc calamine. 



Oxyde, Hatty. 



Vertical prism = 99 56'. Horizontal prism in the 

 direction of the longest diagonal, = 120. Cleavage the 

 same. Hardness = 5.0. Sp. gr. =3.3, 3.6. 



External Characters. Most common colours whit 

 and yellow ; it also occurs green, grey, yellow, and 

 brown. Ha* sometimes a curved striped colour deli- 

 neation. Occurs massive, disseminated, in crusts, sta- 

 lactitic, rcniform, botryoidal, cellular, corroded ; also in 

 distinct concretions, which are scopiform, radiated, or 

 fibrous, granular, and curved lamellar. Sometimes cry- 

 stallized. The following are some of its secondary 

 forms: 



1. Six-sided prism. 2. Flat six-sided prism, bevelled 

 on the terminal planes; the bevelling planes set on the 

 broader lateral planes. This prism is sometimes so flat, 

 that it appears like a longish rectangular four-sided 

 table bevelled on the terminal planes. 3. Acute dou- 

 ble four-sided pyramid, sometimes perfect, sometimes 

 truncated on the summit.*. 4. Acute double four-sided 

 pyramid, acuminated on both extremities, with four 

 planes, which are set on the lateral plnnes, and some* 

 times the summits are truncated. 



Crystals small ; either solitary or scopiformlv aggre. 

 gated". Internally, the lustre alternates from glistening 

 to dull, and lustre pearly, inclining to adamantine. 

 Fracture .-1:1. ill and fine-grained uneven. Alternate* 

 from transparent to translucent on the edges, and 

 opaque. Crystallized varieties as hard as apatite ; the 

 massive and 'opaque softer. Dark-coloured varieties af- 

 i yellowish-grey streak. 



Phyncal Characters. When gently heated, it is 

 strongly electric. 



Chemical Character!. It loses, according to Pelle- 

 tier, about 12 per cent, by ignition ; it is soluble in mu- 

 riatic acid without effervescence ; and the solution gt- 

 latinise* on cooling. 



Rfzbanjr*. 



CunililucHl Parti. Oxide of Zinc, 68.30 

 Silica, . 25.00 



Water, . 4.40 97-70 



Smithton, in Phil. Trans. Part i. for 180S. 

 Geognostic Situation It occurs in small quantities 

 in metalliferous veins, principally along with on 

 lead, in grey-wacke, grey-wacke-slate, and clay-slate ; 

 but most frequently in secondary or floetz limestone, 

 in imbedded masses, and irregular beds. 



Geographic Situation. It occurs in the lead-mines at 

 Waiilockhend ; also in Leicestershire and Flintshire, 

 and in several countries on the Continents of Europe 

 and Asia. 



ACT** <qrt, that IxeaoM the cadmia (ealaroine) ia the furnace, attache* itself to the iron ban in fcrau like a reed, (calamui) it mat 



3 



