226 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



THE VEEMICULITE GROUP OF MINERALS. 



Professor J. P. Cooke, Jr., of Harvard University, has pub- 

 lished in the Proceedings of the American Academy of Arts 

 and Sciences an interesting description of this mineral group. 

 The old name, vermiculite, he applies to the whole group, in- 

 stead of to merely one species, and classes under it the three 

 minerals jefferisite, culsageeite, and hallite. The last two 

 names are new, being applied, the one to a mineral from the 

 Culsagee Mine, in N. C, the other to a micaceous substance 

 from East Nottingham, Pa. All three resemble the micas, 

 and exfoliate remarkably when subjected to heat. The bulk 

 of the paper is taken up with the chemical and optical rela- 

 tions of these minerals, their resemblance to other micas be- 

 ing carefully pointed out. 



H0RBACH1TE A NEW MINERAL. 



A new ore of nickel, described by Knop, has been found 

 in the mines of Horbach, in the Black Forest. Its composi- 

 tion in per cent, is nickel, 11.98 ; iron, 41. 96; sulphur, 45.87. 

 This shows it to be, in all probability, a mixture of the iso- 

 morphous trisulphides of iron and nickel, of a somewhat vari- 

 able character. It seems, from a chemical point of view, to 

 be really a unique species, no similar constitution having 

 ever been observed among native sulphides. The new min- 

 eral, for which the name horbachite is proposed, resembles 

 magnetic pyrites or pyrrhotine in many respects. It forms 

 irregular nodules, of specific gravity 4.43, decidedly magnet- 

 ic, and of a pinchbeck-brown color inclining to steel-gray. 

 It seems to yield up its nickel quite freely, and to be a really 

 valuable ore. Jour. Chem. Soc, January, 1874, 34. 



SCHROCKINGERITE. 



A new mineral, bearing the above name, has been de- 

 scribed by Schrauf. It occurs at Joachimsthal, in small, soft, 

 thin, six-sided plates, implanted on pitchblende. Its color is 

 a light greenish-yellow, and its composition shows it to be a 

 calcio-uranic carbonate. Outwardly it resembles the micas, 

 and it differs in its optical and crystallographic properties 

 from all the calcio-uranic carbonates hitherto known. 21 A, 

 February, 1874, 134. 



