the Ores of Manganese. 135 



streak and their hardness coincide, we may safely consider them 

 as belonging to the same species. Some of the octahedral crys- 

 tals, quoted by Count BOURNON*, for which he proposes the de- 

 nomination of Fer oxyduU manganesien, must also very likely be 

 referred to the brachytypous manganese-ore. He supposes their 

 form to be derived from the regular octahedron, but does not 

 quote in favour of this opinion any decisive proofs, which are 

 rendered necessary, when a species, nearly resembling the varie- 

 ties alluded to, is found to have for its fundamental form a four- 

 sided pyramid so little different from the regular octahedron. 

 Those individuals which have their solid angles replaced by four 

 faces, may perhaps belong to Hausmannite, as is mentioned in 

 the observations annexed to that species, which was likewise not 

 distinguished as a species of its own at the period of publication 

 of Count BOURNON'S Catalogue. 



Braunite is found, both crystalline and massive, at Oehrenstock 

 near Ilmenau, at Elgersburg, Friedrichsroda, and other places 

 in Thuringia, in veins in porphyry, along with pyrolusite and 

 psilomelane. At Leimbach in the county of Mansfeld it was dis- 

 covered in octahedral crystals by Professor H OFFMANN of Halle, 

 in cavities of white quartz, which appear to have been filled ori- 

 ginally with some other substance. The specimens were collect- 

 ed from the masses which were broken for repairing the roads. 

 It occurs also at St Marcel in Piedmont. The locality of Wun- 

 siedel in Bayreuth, given in Mr ALLAN'S cabinet for the varieties 

 of braunite, Figs. 19, and 21, appears to me exceedingly proble- 

 matical ; since, among a vast number of specimens in various col- 

 lections, I have not seen any from that place, while the specimens 

 in the cabinet possess the aspect of those derived from the mines 

 of Thuringia. 



* Catalogue, p. 395. 



