66 



PHYSIOGRAPHY. 



Native Gold. 



3. 



Cube, with edges truncated. 

 Siberia. 



4. 



Dodecahedron. 



Transylvania. 



6. 



Trapezohedron. 

 Siebenburgen. 



7. Fig. 323. 



Siebenburgen. 



Siberia. 



Cleavage, none. Fracture hackly; the cube often hol- 

 low ; the octahedrons either rough or smooth, in combina- 

 tions, generally the latter ; the icositetrahedrons streaked 

 parallel to the edges of combination with the cube and the 

 octahedron. These differences in most cases are not dis- 

 tinctly marked. 



Lustre metallic. Color, various shades of gold-yellow. 

 Streak shining. 



Ductile. Hardness = 2-5 . . . 3-0. Sp. gr. = 14-857, 

 a rolled mass of a high gold-yellow color; 19'2527, melted, 

 HAUY. 



Compound Varieties. Twin-crystals; face of compo- 

 sition parallel, axis of revolution perpendicular, to a face 

 of the octahedron ; pretty frequent, particularly irr the icos- 

 itetrahedrons, as represented in 



