Hidden and Mackintosh Occu/rrento of Poly crate. .'Jo:; 



locality is given and the mineraJ here described is therein re- 

 ferred to as "a member, as jet unidentified, of the samarskite 

 up." No analysis wsb then attempted, as the material on 

 hand was impure, and insufficient; we hoped for purer and 

 larger masses as the locality became developed, dp to July, 

 (.889, the character of the mineral was not fully determined, and 

 a very considerable amount of labor had been fruitlessly ex 

 pended in an endeavor to find it and xenotime in commer- 

 cial quantities. Altogether only about 100 grams had been 

 found, the work being carried on after the manner of placer 

 gold-washing. The locality is on the Davis land, in Bender* 

 Bon Co., North Carolina, at a place on the "old Greenville 

 Road" where it is crossed by a decomposing and low lying 

 granitic formation. It is about four miles from Zirconia (a 

 railroad station), and not far from the South Carolina state 

 line. Tin iated minerals are zircon, monazite, xenotime, 



cyrtolite and magnetite. Of the first four of these about 

 <>ne ounce would be found, in the concentrates, upon washing 

 about one cubic yard of the kaolinized granite. 



This mineral is invariably found in separate crystals, no mas- 

 Bive variety being as yet observed, and they have a type of form 

 atly resembling figure 434, of polycrase, in Dana's System 

 of Mineralogy. They are always more or less altered on the 

 surface to a pale yellow gummite-like substance, and the line of 

 demarcation from the unaltered to the altered mineral is very 

 sharply defined, no intermediate stages of alteration being e\ T i- 

 denced. 



Xo satisfactory measurements of angles were possible. The 

 crystals were small, thin, square flattened prisms, with several 

 terminal planes (in one zone only). One brachydome had an 

 angle of about 133^° on the braehypinacoid. One twin, par- 

 allel to the unit brachydome, was observed quite perfectly de- 

 veloped. 



The pure mineral is nearly coal-black, with a brownish yel- 

 low translucence through thin edges. Its fracture is small con- 

 choidal with a brilliant sub-metallic to resinous luster. No 

 cleavage was noticed. The density as taken on a gram of care- 

 fully selected grains of the broken dark internal cores was 

 found to be 4 7s. Another determination on a single mass 

 gave 4724. Its hardness = 5 - 5. Streak and powder light 

 yellowish brown, approaching to white. When heated it 

 decrepitates slightly and becomes dark brown. It is infusible. 



The material analysed was the same as that upon which the 

 higher density was determined and the results were ae follows : 



