VALLEY OF THE MISSISSIPPI. 01 



bouring mountains of the hot springs, which originate 

 in t':is formation, I have seen specimens of magnetic 

 iron-ore, like that of the Hudson and New Jersey. 

 On the road to the springs, also, I have obtained spe- 

 cimens of a dark grey amphibolic rock, strongly 

 magnetic when heated, of a very close grain, 



steel. Its color, very similar to that of Cacholong or porce- 

 lain, is milk-white, acquiring a faint ferruginous tinge by ex- 

 posure to the weather, it then more readily cleaves, and becomes 

 somewhat absorbent. Its specific gravity is 2,60. Before the 

 blow-pipe it is perfectly infusible, and unlike chalcedony and 

 flint still retains its translucence. With potash it dissolves 

 into a white enamel, but does not form glass. Analyzed in 

 the manner described by Klaproth, which it is not here neces- 

 sary to repeat, it afforded in the hundred parts, si lex 86, 

 alumine 1,50, lime 2, oxid of iron 5, and volatile matter with 

 a trace of carbonic acid 4. 



Geological situation and locality.} It is found in the transi- 

 tion mountains of the Washita, a few miles from the hot- 

 springs, and in the Mazern mountains, at the sources of the 

 Kiamesha of Red river, forming schistose beds, which alternate 

 with slate-clay and grauwacke-slate. Passing apparently 

 into a translucent hornstone, still retaining the slaty cleavage, 

 and often breaking into rhombic fragments, similar to felspar. 

 This mineral is the " hone-stone," spoken of by Hunter and 

 Dunbar, but sufficiently distinct from Novaculite, although 

 when weathered or deteriorated by foreign admixture, it be« 

 comes in some degree, suitable for that purpose. Its cleavage 

 appears to be produced by the iron, which it essentially contains, 

 and its milky color is probably derived from the carbonate of 

 lime. 



