262 BULLETIN 131, UNITED STATES NATIONAL MUSEUM 



lent polish and the green malachite and deep red hematite make a 

 pleasing combination which may be suitable for use as a gem or 

 ornamental stone. 69 



BLAINE COUNTY 



Malachite occurs in small amounts in the oxidized portions of 

 many veins. Its most noteworthy occurrence in the county is in 

 the Clyde district, where the green carbonate occurs in stains and 

 crusts with azurite and chrysocolla making up the oxidized copper 

 ore of the Copper Bluff prospect in Basinger Canyon northeast of 

 Clyde. 70 



CUSTER COUNTY 



In the Alder Creek (Mackay) district malachite is a persistent 

 though subordinate mineral throughout the oxidized ores, where 

 it occurs in intimate association with azurite, chrysocolla, broch- 

 anthite, and other secondary copper minerals. It is likely to be 

 confused with brochatithite which, however, is duller green and 

 does not effervesce with acid. The malachite commonly occurs as 

 bunches of irregular form in the silicate ores and as crusts alter- 

 nating with azurite in tabular and lenticular masses. 71 In the gold- 

 copper deposits of the Loon Creek district, and the silver-copper 

 mines of the Bayhorse district in the northwestern part of the 

 county, malachite is common as a stain in the outcrops. In the 

 Ramshorn and Hoosier mines it forms delicate green velvety crusts 

 in cavities in partly oxidized tetrahedrite. In the Copper Basin 

 district at the head of the east fork of Big Lost River malachite 

 occurs with azurite as blebs, bunches, and veinlets in amorphous 

 chrysocolla in the ore of the Parallel tunnel of the Reed and David- 

 son mine. On the 180-foot level on the shaft of the same mine the 

 ore consists mainly of malachite both of light pea-green and dark 

 emerald-green color, the darker occurring as crusts on the lighter 

 and the whole concentrically arranged. Similar ore occurs in the 

 Rosenkrans property. 72 



FREMONT COUNTY 



In the Skull Canyon district malachite is the most conspicuous 

 mineral of the ore of the mine of the Weimer Copper Co., 2 miles 

 east of Kaufman, where it forms incrustations along fractures or 

 beautiful needle crystals scattered through the finely vesicular por- 

 tions of the vein and in the small vugs which occur sparsely in the 

 firmer parts. It is contained in a gangue of hematite varying from 

 soft ocher to hard jaspery material. 73 A specimen from this mine 



» U. S. Geol. Survey. Mineral Resources for 1909, pt. 2, pp. 804-805. 

 'o J. B. Umpleby. U. S. Geol. Survey, Prof. Paper 97, p. 113, 1917. 

 «i J. B. Umpleby. U. S. Geol. Survey, Prof. Paper 97, p. 54, 1917. 

 " J. B. Umpleby. U. S. Geol. Survey, Prof. Paper 97, p. 105, 1917. 

 7 » J. B. Umpleby. U. S. Geol. Survey, Prof. Paper 97, p. 112, 1917. 



