PHYSIOGRAPHY. 75 



Blue Malachite. 



Brittle. Hardness = 3-5 ... 4-0. Sp. gr. = 3-831, 

 crystals from Chessy. 



Compound Varieties. Globular, reniform, botryoidal, 

 stalactitic shapes, implanted and imbedded; surface drusy 

 and rough ; composition columnar, more or less perfect and 

 distinct, faces of composition rough. Massive : composi- 

 tion columnar, more rarely granular. Sometimes in an 

 earthy state. 



1. Blue Malachite is soluble with effervescence in nitric acid, becomes 

 black if exposed alone to high decrees of temperature, melts upon char- 

 coal, and colors glass of borax green in the oxidating flame. 



2. Analysis. 



By KLAPROTH. By VAUQUELIN. 

 Copper . . 56-00 . . 56-00 



Oxygen . . 14-00 . . 12-50 

 Carbonic acid . 24-00 . . 25-00 

 Water . . 6-00 . . 6-50 



3. It is met with in veins and beds, included in rocks of different ages. 

 It is generally accompanied by Green Malachite and some other ores of 

 copper. Occasionally it is so intimately connected with Green Mala- 

 chite, that crystals of the form of the Blue Malachite consist entirely, or 

 at least with only the exception of a thin film on the surface of the deli- 

 cate green fibres, of Green Malachite. It is often engaged in ochrey va- 

 rieties of Limonite, and associated with White Lead-ore, Galena and 

 Cobalt-bloom. 



4. The most beautifully crystallized varieties are found in a bed in sec- 

 ondary mountains at Chessy near Lyons in France. Fine crystals are 

 brought from Siberia. Very delicate, but small crystals, are found at 

 Oravitza in the Bannat. Blue Malachite occurs also in Thuringia, Hes- 

 sia, the Hartz, Silesia, Tyrol, Spain, Chili, Peru, and at several places in 

 England and Scotland. 



The United Stales afford no very interesting deposits of this species. 

 The best specimens are found in Pennsylvania at the Perkiomen lead 

 mine, where it occurs in small crystals along with Galena, Blende and 

 White Lead-Ore. 



