[1847. The new Mineral Newboldite. 1131 



It occurs in very small nests and Veins in masses of milk quartz. 

 With one of the specimens of milk quartz there occurs amass of bluish 

 sulphate of Baryta, and another specimen is in a bluish very fine gra- 

 nular mass of sulphate of lime. 



Its specific gravity I should estimate at about 4.25, to 4.50, calcu- 

 lated from a piece which was about half matrix, but this is a mere 

 approximation. 



In the tube and bulb tube it decrepitates and flies to pieces with a 

 complete explosion, sending the fragments sharply into the face and 

 eyes when tried on platina foil, as soon as heated ; these fragments are 

 mostly imperfectly cubical or rhomboidal. 



It was found to contain about 1 per cent, of water when reduced to 

 powder. 



Nothing sublimes from it at the red heat of glass ; but when driving 

 off the water a slight odour of sulphur seems apparent from the 

 crucible. 



Blowpipe. — Alone. — A small fragment is infusible, but becomes of 

 a dirty yellowish white, and is not magnetic. This, apart from its sulphur 

 (subsequently shown) at once distinguishes it from Spathose Iron, for 

 some of the green semi-transparent varieties of which, from its colour 

 and decrepitation, it might be mistaken on mere inspection. 



With Borax it is not very fusible ; the bead transparent, yellowish^ 

 and slightly tinged with green. 



With Soda fuses to a dirty brownish opaque bead ; nothing is re- 

 duced from it j when moistened and a little fresh Soda added, the bead 

 gives out the smell of sulphuretted hydrogen common to all the sul- 

 phates and sulphurets when heated with Soda, and it discolours silver 

 foil. 



With phosphate of Soda. — On charcoal, and the cake transferred to 

 platina wire, a dull milk-white semi-transparent bead. 



The powder saturated with Nitrate of Cobalt, and heated on plati- 

 na foil, is of a dull brown. 



Via Humida. — It dissolves readily in the mineral acids. Acetic acid 

 does not appear to affect it. With concentrated hydrochloric and 

 sulphuric acids much sulphuretted hydrogen is evolved. Boiled in 

 nitro-hydrochloric acid it dissolves rapidly without evolution of sul- 

 phuretted hydrogen in any considerable quantity, if at all, and leaves 



