19S 



Outlines of the Mineralogy and Geology 



It is brittle, 



E 



L 



It is easily fi-augible. 



The fragments are indeterminately angular and not particu^ 

 larly sharp edged. 



Its specifick gravity is from 3.000 to S.5M, 



Chymical Character. 

 Uefore the blowpipe it fuses into a black scoria^ and becomes 



magnetick. 



Geological Situation and Localities. 



It occurs in alluvial soil, at Cambridge, Briditon, Charles 



& 



) 



town, Woburn, Dorchester beach, &c. 



MemarJcs, 



Although Nodular Ironstone has many localities, it is not an 



abundant mineral in this vicinity ; solitary specimens only 



are 



found. 



SPECIES YL^aiRBOmTE OF IROJK^, 



Carbonate of Iron, Ckaveland, p. 50!. Sparry Ironstone, Jameson, vol. u 

 p. 308. SpaiTv Iron Ore, Kirwan, vol. n. p. 190. Idem, Mdn. 



External Characters, 



•A 



Its colour is red ; of which it occurs cochineal red and brown- 



ish red. 



These colours, by long exposure to the atmosphere 

 verted into blackish brown. 



It is faintly glimmering and dull. 

 It is opaque. 



; 



are con- 



