METAL* 



287 



22. MERCURY 



Mercury occurs native, alloyed with silver, and in combi- 

 nation with sulphur, chlorine, or iodine. Its ores are com- 

 pletely volatile, excepting the one containing silver. 



NATIVE MERCURY. ^ i? ^ V\<J|.\ji 



Monometric ; in octahedrons. Occurs in fluid globule 

 scattered through the gangue. Color tin-white. Gr=13*6 

 Becomes solid and crystallizes at a temperature of— 39° F. 



Mercury, or quicksilver as it is often called, (a translation 

 of the old name " argentum vivum,") is entirely volatile be- 

 fore the blowpipe, and dissolves readily in nitric acid. 



Obs. Native mercury is a rare mineral, yet is met with 

 at the different mines of this metal, at Almaden in Spain, 

 Idria in Carniola, (Austria,) and also in Hungary and Peru. 

 It is usually in disseminated globules, but is sometimes ac- 

 cumulated in cavities so as to be dipped up in pails. 



Uses. Mercury is used for the extraction of gold and sil- 

 ver ores, and is exported in large quantities to South Amer- 

 ica. It is also employed for silvering mirrors, for thermome- 

 ters and barometers, and for various purposes connected with 

 medicine and the arts. 



Native Amalgam. This mineral is a compound of mercury and sil- 

 ver, containing 64 to 72 per cent, of mercury, and occurring in silver- * « \i 

 white dodecahedrons. H=2— 25. Gr=105— 14. Principally from b. ^ n 

 the Palatinate; also from Hungary and Sweden.*} The arquerj te of f^V^ta. 

 Berthier is an amalgam from Coquimbo, containing only 135 per cent. * J 

 of silver. 



cinnabar. — Sulphuret of Mercury. -il*r 



Rhombohedral. R : R=71° 47'. Cleavage transverse, 

 highly perfect. Crystals often tabular, or six-sided prisms. 

 Also massive, and in earthy coatings. 



Luster unmetallic, adamantine in crystals ; often dull. 

 Color bright red to brownish-red, and brownish-black. 

 Streak red. Subtransparent to nearly opaque. H=2 — 2*5. 

 Gr=6*7— 8-2. Sectile. 



Composition : when pure, mercury 86*29, sulphur 13*71 ; 



In what condition does mercury occur ? What is a characteristic of 

 its ores? Describe native mercury 1 Where is it found? For what 

 .8 it used ? What are the physical characters of cinnabar 1 



