OF JAMES SMITUSON. 



161 



No. 2952. Unknown plated metallic ore, said to come from 

 the Ilartz, in my cabinet marked No. 2952. 



1. Its color is grey, like that of lead or sulphuret of zinc. 



2. It is brittle. 



3. Has the metallic gloss and opacity. 



4. Per se on the charcoal decrepitates greatly. 



5. With borax melts, effervesces, emits a white sraoke, and exhales, 

 leaving a small bull of white metal, which appears to be lead, as it is en- 

 tirely fluid when not very hot. 



C' Molted in tho gold spoon with carbonate of Fodii produces a greyish 

 mass; water added ibrmcd a black powder, and tho solution stained silver 

 only very slightly. This solution being mixed with nitric acid produced 

 but a very slight smell of sulphide of soda, and the black powder continued 

 insoluble. 



7. Reduced to po\;vder and very strong nitric acid poured on it there was 

 no effect, but gradually a very gentle effervescence took place, the ore was 

 decomposed and sulphur became visible. 



8. A small bit held at tho end of a clay-slip in the flame of the lamp it 

 partially molts and glazes tho clay-bit around itself. The flame being 

 directed on it by tho blowpipe it melts to a metallic ball and spreads a 

 yellow gloss on tho clay. The little metallic button, being separated from 

 the clay-bit and beat on the steel plate, extended to a thin and hot platg 

 which was flexible like lead. 



9. The solution No. 7 afforded colorless octahedral crystals. 



No. 3093— Black slate. 



1. It feels very light. 



2. Tho lens shows particles of mica in it. 



3. Before the blowpipe it takes fire and burns with a flame like coals, 

 but does not molt, leaving a greyish mass of its former shape and volume. 

 This muss is as hard as the slate. The burned bit put into muriatic acid 

 produced a smell of liver of sulphur. 



4. Another burned bit at a strong fire melted quickly at tho angles to a 

 glossy black matter. It did not stain silver — was not drawn by the mag- 

 net. Put on to silver with a drop of muriatic acid it made some small 

 spots on it. 



5. Put into pure muriatic acid it effervesced so slowly as to be scarcely 

 visible, and the smaller bits did not fall to powder or soften. Put in pow- 

 der into muriatic acid the effervescence was more sensible, but I could not 

 not find that the solution reddened sensibly the flame of a candle. 



N. B. — This might prove a new test. 



No. 3912. — Carbonate of lime. St. Andreasberg. 



f^^ 



oc == 90° 



no = 127° 30' 



nc = 142° 30' 



From tho above figures it is probable that the faces n are those of the 

 rhombohedron, h, fig 7, Haiiy, though the angles differ by 3° 15^ 



[_AR:0 = 127° 15'. I.] 



