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tremcly varied in character, and in the per centage of iron 
they contain ; they generally make a good quality of iron, 
possessing neither cold shortness nor red shortness in excess. 
They contain from 20 to 35, and in some cases even 40 per 
cent, of iron. The carbonaceous iron stones or blackbands, 
as they are termed, are most largely developed in Scotland 
and North Staffordshire, although also found in North 
Wales, South Wales locally, in South Staffordshire, and 
elsewhere. They contain, when raw, from 20 to 38 per 
cent, of iron ; and when calcined they sometimes reach as 
high as from 60 to 65 per cent. They contain a large pro- 
portion of carbonaceous matter, varying from 6 to 25 per 
cent. This class of ironstone produces a cold short, but 
extremely fluid iron, most probably from the phosphoric 
acid which generally enters into their composition. 
The haematites, or red oxides, are also sub-divided into two 
principal classes. 
1st. The comparatively pure oxides of the Ulverstone and 
Whitehaven districts. 
2nd. The calcareous ironstones of the Forest of Dean. 
Both these varieties are remarkable for the red short 
tendency of the iron they produce ; but which, nevertheless, 
stands high, from its great strength and from its peculiar 
fitness for tin plates, &c. The haematites of Ulverstone 
and Whitehaven contain from 55 to 68 per cent, of iron, 
those of the Forest of Dean from 35 to 50 per cent. 
Besides these two great classes, there are also the brown 
haematites of Alston Moor and Durham, corresponding in 
some degree to those of Belgium and the haematites of the 
older rocks of Devon, Cornwall, and West Somerset. The 
first of these contain from 30 to 45 per cent, of iron, and 
make a fluid, and comparatively cold, short iron. The second 
are never used, except as a mixture with other ores, and 
rarely contain more than from 45 to 50 per cent, of iron. 
s 2 
