MINERALOGY. 



509 



COM co vi 

 MimrciT. 



ComtitueMt Parts. Silver, 24.64 



Muriatic Acid, 8.28 

 Alumina, with a 

 trace of copper, 67.08100.00 



Klaproth, Beit. b. i. s. 137. 



Geognostic and Geographic Situations. It is found 

 in veins that traverse transition rocks at Andreasberg 

 in the Harta. 



Gius n_CORNEOUS MERCURY. 



Perl Kerate, Mohs. 

 One axis. Cleavage very indistinct. Hardness, = 

 1.0. 2.0. Sp. gr. = 



This genus contains one species, vie. Pyramidal Cor- 

 neous Mercury. 



Pyramid*) ' PYRAMIDAL CORNEOUS MERCURY, Jameson Py. 

 eorMoui ramidales Perl Kerate, Moht. Quecksilber Horners, 

 mercury. Werner. Mercure muriate, Hauy. 



Pyramid unknown. Cleavage indistinct axifrangi- 

 ble, sectile. 



External Characters Colour grey. Occurs very 

 rarely massive, almost always in small vesicle* crystal- 

 Used in the interior. The crystals are the following : 



1 . Rectangular four-sided prism, acuminated on the 

 extremities with four plane*, which are set on the la- 

 teral planes. 2. Rectangular four-sided prism, acumi- 

 nated with four plane*, which are set on the lateral 

 xlfM 3. Double four-skied pyramid. 



Crystals always so minute that is is with difficulty their 

 torms can be determined. External surface sometimes 

 smooth, sometimes drusy, and in general shining and 

 adamantine. Internally shining, with an adamantine 

 lustre. Has a single cleavage, which appears to be 

 parallel with the terminal planes of the prism. Faintly 

 translucent, or only translucent on the edge*. Sectile, 

 and easily frangible. 



Chemical Characters It is totally volatilized before 

 the blowpipe, and emits a garlic smell. It is soluble 

 in water, and the solution mixed with lime-water gives 

 an orange-coloured precipitate. 

 Constituent Parts. Oxide of Mercury, 76.00 

 Muriatic Acid, 16.40 

 Sulphuric Acid, 7.60100.00 



Klaprolh. 



Gregnostic Situation In the quicksilver mines of 

 the Palatinate, and Dutch y of Deux Pont*. 



Geographic Situation. It occurs in Bohemia, Deux 

 Pouts, Palatinate, Upper Hesaia; and at Alinaden in 

 Spain. 



OiDa IV .MALACHITE. 



sUii- No metallic lustre. Streak blue, green, brown. If 



CHITE. white, the specific gravity is 2.2 and less. Colour not 

 inclining to yellow. Cleavage is neither distinctly axi- 

 frangible nor prismatoidal. Hardness, ranges tri... 

 to 5. If the streak is brown, the hardness is less than 

 3.5. Specific gravity range* from 2 to 4.6 ; if it is leas 

 than 3.2, the hardness is below S. 



This Order contains four Genera, viz. 1. Copper- 

 Green, 2. Malachite, 3. Olivenite, and, 4. Emerald- 

 Copper. 



Coma- GMUS I COPPER-GREEN. 



oasx. Trauben Malachit, Mohs. 



Reniform ; botryoidal. Streak white. Hardness 

 = 2.0,_ , ravity = 2 .0, 2.2 



This Genu* contains one Species, viz. Common Cop- 

 per-Green. 



2 



Common 



1. COMMON COPPER-GREEN, or CHRYSOCOLLA. Oryctogno- 

 Jamesoii. Untheilbarer Trauben Malachit, Mohs. Kup- *> 

 fergriin, Werner. 



No cleavage. copper- 



This species is divided into three subspecies, viz. green. 

 1. Conchoidal Copper-Green, 2. Earthy Iron-shot Cop- 

 per-Green, 3 Slaggy Iron-shot Copper-green. 



FIRST SUBSPECIES. 



CONCHOIDAL COPPER-GREEN, Jameson Kupfergriin, Conchoidal 

 Werner. copper- 



External Characters. Principal colour green. Oc- 

 curs massive, disseminated, and coating or incnisting 

 malachite, sometimes small reniform, and small botryoid- 

 al. Internally shining, passing into glistening ; lustre 

 resinous. Fracture small conchoidaL , Fragments 

 indeterminate angular, and more or less sharp-edged. 

 It alternates from translucent to translucent on the 

 edges. Colour not changed in the streak. Easily 

 frangible, and rather brittle. 



Chemical Character!. Before the blowpipe, it be- 

 comes first blaek, then brown, but is infusible. 

 Conilituenl Parti. Copper, . 40.00 

 Oxygen, . 10.00 

 Carbonic Acid, 7.00 

 Water, . 17.00 

 Silica, . . 26.0000.100 



Klaproth, Beit. b. i. s. 36. 



Geognostic Situation. It is met with in the same 

 geognostic situations as malachite. 



Geographic Situation. It occurs in Cornwall, along 

 with olivenite, and also in the vale of Newlands, near 

 eswick. 



SILICEOUS COPPER, Jameson. Kieselkupfer, Joh*. s,licous 

 Its colours are asparagus-green, and celandine-green, copper. 



inclining to sky-blue. Occurs in crusts. Dull, laintly 



glistening, and resinous. Fracture even or earthy. 



ipaque, or rarely translucent on the edges. Soft. 

 Constituent Part*. Copper, 37.8. Oxygen, 8. Water, 



21.8. Silica, 29; and Sulphate of Lime; 3. 



SECOND SUBSPECIES. 



EARTHY IRONSIIOT COPPER-GREEN, Jameson. Er- u artby 

 diches eiscnschiisxiges Kupfergriin, Werner. ironthot 



External Characteri. Colour olive-green, which c PI* r - 

 sometimes passes into pistachio-green, and inclines to g ' 

 leek-green. Occurs massive, and in crusts. Generally 

 i >f friable consistence, and composed of dull, dusty 

 panicles, which are more or less cohering, and that do 

 not soil. Compact varieties have an earthy fracture. 

 Opaque. Very soft, passing into friable. Sectile, and 

 easily frangible. 



THIRD SUBSPECIES. 



SLAOOY IRONSIIOT COPPER.GREEN, Jameson siw 



Schlackiges-eisenschusjiges Kupfergriin. Werner. ironfhot 



External Characters. It is blackish-green, and dark cop P* r - 

 pistachio-green. Occurs massive and disseminated. 

 Internally shining, glistening, lustre resinous. Frac- 

 ture small conchoidaL Fragments indeterminate an- 

 gular, and more or less sharp-edged. Opaque. Colour 

 becomes paler in the streak. Soft, verging into very 

 soft. Easily frangible. 



Constituent Parts. It is probably a compound of 

 Conchoidal Copper-Green and Oxide of Iron. 



