FLINT 



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FLEXIBLE SANDSTONE. A micaceous or talcose sandstone, possessing 

 considerable elasticity, so as to bend to and fro with gentle pressure. It is found in 

 the diamond-bearing districts of Brazil, in the United States, and near Delhi. See 

 AETICULITE ; ITACOLTJMITE. 



FLEXIBLE SILVER ORE. A name for Stephanite. See SILVER. 



FLINT. (Pierre a fusil, Fr. ; Feuerstein, Ger.) A massive impure variety of silica 

 allied to chalcedony. It forms a connecting link between quartz and opal, since it 

 consists, according to Fuchs, of an intimate mixture in varying proportions of the two 

 forms of silica the crystalline or insoluble, and the non-crystalline or soluble; 

 the latter being readily separated by solution of caustic potash. The colours of 

 flint, which are usually various shades of grey, brown, or black, are entirely removed 

 by calcination, the flint thus becoming white and opaque : whence the colour is com- 



