140 



minute quartz crystals, frequently very transparent, attached 

 to this ore ; which on the dark ground deceive us with the 

 idea of crystallized iron ore : however, with the help of a lens, 

 it may often be discovered whether we are right or not, by the 

 form of the crystals. The latter, although a seeming modifi- 

 cation of carbonate of lime, appear to be slightly magnetic. 

 It is a very curious circumstance that this should so gene- 

 rally resemble, in the form of its crystal, the carbonates of 

 lime, this being like a flattened tequiaxe with various modi- 

 fications. Rome de Lisle's, p. 4. f. 62. is the nearest re- 

 sembling it, wanting only the 6 alternating narrow faces. 

 The fracture is intennediate between glassy and splintery, 

 and when fresh broken it shows an iron or steel-like lustre. 

 The outsides of the crystals are of a darker iron or steel-grey 

 with much gloss or polish ; the edges of some resemble 

 blued steel, and sometimes reflect other colours. They 

 stand edgeways on the matrix ; which makes this hue more 

 conspicuous, and adds much to the beauty of the specimen, 

 especially when magnified. 



We presume this is the same as the beautiful iron ore 

 from Elba, now first noticed in England. 



