394 Scientific Intelligence. — Mineralogy, 



12. On Anthracite, or Glance-Coal. By A. Breithaupt. — 

 It has been long known that anthracite, or glance-coal, occurs 

 chiefly in the intermediary formations ; but opinions vary as to 

 its mode of existence in these formations. In all the localities 

 in which M. Breithaupt had an opportunity of observing it, 

 such as Wezzelstein and Saalfeld, Lischuriz near Gerz, &c., it 

 presented itself in veins, never in beds. In the autumn of 1826, 

 M. de Warnsdorf discovered in the slate quarries of Wurzbach, 

 near Lobenstein, in Voigtland, several quartzose veins, one of 

 which contained a very interesting variety of anthracite. It oc- 

 cuts in isolated rods, which, like all the crystalline forms of 

 this species, go from one of the sides to the other in a nearly 

 perpendicular direction. These flakes are surrounded by 

 quartzy fibres, perpendicular to their lateral surfaces, and conse- 

 quently parallel to the plane of the vein, which seems to prove 

 that their formation is posterior to that of the anthracite. M. 

 Breithaupt enumerates all the reasons which induce him to 

 consider these flakes as being really crystallized, and to refer the 

 anthracite crystals to the system of crystallization of the prism, 

 or rhomboidal octahedron. 



13. On the probable Occurrence of the Diamond in Siberia. — 

 It is expected that diamonds will be found in Siberia. A letter 

 written by a travelling naturalist to the rector of the University 

 of Dorpat, contains the following details : — The platiniferous 

 sand of Nischni Toura bears a striking resemblance to that of 

 Brazil, in which diamonds are commonly met with. According 

 to the description given of it by M. Eschwege, this sand is 

 principally composed of rolled fragments of hydrate of iron and 

 jasper, and contains more platina than gold. The Nischni Toura 

 sand is visibly formed of the same component parts ; and the 

 presence of hydrate of iron in it is so much the more remarkable, 

 that it is in a conglomerate of the same kind that the Brazilian 

 diamonds occur, that these two minerals are not associated 

 merely by accident, but are the debris of one and the same for- 

 mation. The author of this letter explains the reason why he 

 could not engage in the search for diamonds, in a place where 

 he is convinced they will be found. He communicated his ob- 

 servations to the director of Nischni Toura, who appeared dis- 

 posed to commence operations. — Zeitschrif't fur Mineralogie, 

 February, 18S7. 



