256 BISMUTH. 



— Its colour is dark lead-grey, with a shining metallic lustra. It 

 occurs disseminated, and crystalized in oblique four or six-sided 

 acicular prisms. It is opaque, brittle, and yields easily to the 

 knife. The specific gravity is 6-2. It fuses before the blow-pipe 

 into a steel -grey globule. Its constituents are bismuth 43'2, lead 

 •24-3, copper 12*1, sulphur 11*3, nickel 1*5, tellurium 1-3, gold 

 07 "9. This variety occurs near Beresof, in Siberia, imbedded in 

 rhomboidal quartz, which in the specimen here represented (PL 

 XXXIII. fig. 4,) is tinged with carbonate of copper. 



Cupreous Bismuth. — Its colour is pale lead-grey, with a yel- 

 lowish or reddish tarnish. It occurs massive and in small acicular 

 scopiformly aggregated crystals. The lustre is shining and metallic. 

 It is soft, and yields easily to the knife. It contains, bismuth 47, 

 copper 47, sulphur 60. It has hitherto been found only in the 

 principality of Furstenberg, and is extremely rare. 



Sp. 3. Bismuth Ochre. — Wismuthoker, Werner; Bismuth 

 oxyde, Hamj. — Its colour is straw- yellow. Its structure is lami- 

 nar, fin-grained, or earthy, with a glimmering lustre. It is opaque, 

 very soft, and sometimes friable. Its specific gravity is4 # 37. It 

 dissolves with effervescence in acids. It is easily reduced before 

 the blow-pipe, on charcoal. Its constituents are, oxide of bismuth 

 86'3, oxide of iron 5'2, carbonic acid 4- 1, water 3*4. It is found 

 at St. Agnes, in Cornwall. 



Bismuth, when pure, has a reddish-white colour, and its texture 

 is foliated. Its specific gravity is 9*8. It is very brittle, breaks 

 under the hammer, and cannot be drawn into wire. It is very- 

 fusible, and melts at a temperature of 476° Fahrenheit ; by a 

 strong heat it is volatilized. If it be exposed to the air while in 

 fusion, it attracts oxygen ; a greenish-grey powder being formed 

 on its surface. Bismuth takes fire and burns with a blue flame 

 at a higher temperature, and a yellow oxide is obtained, known by 

 the name of flowers of bismuth. When bismuth, in a state of fine 

 division, is exposed to chlorine gas, it takes fire, burns with a pale 

 blue light, and is converted into a chloride. Nitric acid acts pow- 

 erfully on bismuth, oxidating and dissolving it, while nitric oxide 

 is disengaged, and a considerable heat produced. Sulphuric ann 

 muriatic acids, have comparatively little action on bismuth. Bis- 



