420 BULLETIN 131, UNITED STATES NATIONAL MUSEUM 



which contains either chlorine or phosphoric acid and the source of 

 these radicles is not known. The pyromorphite is habitually a soli- 

 tary mineral and is seldom immediately associated with other lead 

 minerals. One specimen from the Hercules mine contains green 

 crystals of pyromorphite scattered through crystalline white cerusite 

 like phenocrysts in a porphyry. A specimen of white cerusite from 

 the Stewart mine is coated on one side with a thin crust of green 

 pyromorphite. White pyromorphite is associated with the plattner- 

 ite from the You Like mine and pinkish pyromorphite occurred with 

 galena in the Caledonia mine. 



The following localities for this mineral have been noted in the 

 district : 



The Hercules mine, above Burke, furnished numerous specimens 

 of pyromorphite in well-defined green prismatic crystals, some of 

 them of fairly large size. Some single crystals have been obtained 

 which are 3 cm. long by 1 cm. in diameter, a few of which are hollow 

 tubes. 



Fine pyromorphite is reported to be common or abundant in the 

 Ambergris mine, on the Ninemile Creek side of the ridge near the 

 Hercules mine. None of this has been seen by the writer. Good speci- 

 mens are also reported from the Tamarack and Custer mine. 



This mineral is common in the upper workings of the Standard 

 and Mammoth mines at Mace. Specimens showing deep green pris- 

 matic crystals have been collected from the dump of one of the upper- 

 most tunnels of the Standard and from the dump of the No. 2 tunnel 

 of the Mammoth. A large amount of this mineral was obtained in a 

 seam along a fault cut by a drift from the No. 2 tunnel of the Mammoth 

 mine and specimens may be obtained here as long as the tunnel re- 

 mains open. 



To judge from reports and from the material remaining in the 

 dumps pyromorphite was the principal secondary lead mineral in 

 the upper portion of the Blackbear ore body at Blackbear. There 

 are specimens consisting of thin drusy coatings and massive green 

 pieces of the mineral available on the dumps of this mine. 



George Huston reports that at one time a mine car full of pyro- 

 morphite was taken from a lead bearing vein in the Snowstorm 

 copper mine at Mullan. 



One of the principal localities for the lead phosphate in the district 

 is the Little Giant mine near Mullan. This prospect is reached by a 

 dim trail which ascends the mountain south from the Mullan cem- 

 etery. This trail is shown on the topographic map (United States 

 Geological Survey Coeur d'Alene special topographic sheet) and 

 terminates at the tunnel which extends into the ridge in an easterly 

 direction at an elevation of about 4,750 feet on the east side of a small 

 stream known as Silver Creek, which turns sharply west and descends 



