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are easily distinguished. The fractured parts have some- 
thing of a columnar radiation; but very indistinctly and 
massively incorporated, and the fracture is otherwise small 
or largish, irregularly splintery, without any sign of in- 
ternal crystallizational fracture. This is so peculiar to 
Carbonate of Barytes, that it was chiefly known from other 
substances by this mark, before it was found formed in ex- 
ternal crystals, although that had not been particularly 
described. I have a large piece of radiating Carbonate of 
Lime from my kind friend F. Hall, Esq., of Arkendale, 
fourteen inches long, on the face of which the appearance so 
far corresponds with Carbonate of Barytes, that many good 
mineralogists have doubted which it really is; but the 
fracture of Carbonate of Lime soon exposes it. Carbonate 
of Barytes, or Witherite, may thus be in part known by its 
fracture. I have had dark specimens with Pyrites in it so 
coloured by the Iron, that, for want of the above observa- 
tion, they would not have been known from Carbonate of 
Lime. 
