Manganeje. 349 



ftone, of a fparry texture, and fcarcely mag- 

 netic even after roafting, foluble with effer- 

 vefcence in nitrous acid, and affording a 

 colourlefs folution, which folution, with mild 

 alkalis, gave a white precipitate, and the pre- 

 cipitate, when heated, presently grew blacks 

 a fure criterion of manganefe. Mem. Stock, 



9. Mr Lapeiroufe found this white ore in 

 the form of a fpungy efflorefcence, vegetating 

 on the furface of fome iron ores, particularly 

 haematites. 



10. It has been feen alfo by Mr. Rinman 

 in the form of a calcareous fpar, of the colour 

 of rofin^ and fomewhat {tuning, in fome 

 places covered over with a footy powder, 

 and in thin pieces femi-tranfparent at the 

 edges, and not hard enough to ftrike fire with 

 fteel ; nitrous acid diflblves it almoft intirely, 

 with mild alkalis the folution gives a white 

 precipitate, which blackens when heated. It 

 confifts of manganefe imbodied in zeolyte, it 

 melts perfe with the blow pipe into a whitifh 

 grey porous flag, and with the addition of 

 calcined borax gives a garnet coloured glafs. 



11. Many of white fparry iron ores may 

 alfo be claffed among the ores of manga- 



nefe, 



