Dr. Mac Culloch on Mineral Veins. 205 



the phosphoric acids are so hke, and all the points of analogy 

 between sulphur and phosphorus are so strong, that it is safe to 

 infer that phosphurets might be procured in the moist way as 

 well as sulphurets. 



In now examining the evidence which nature affords from 

 the intimate association that exists between certain metallic 

 minerals and those earthy ones which are ascertained to be of 

 aqueous origin, it may be remarked that the chief of these 

 latter are calcareous spar and quartz. Barytes and fluor are 

 less conspicuous in this respect. The union with calcareous 

 spar is rather more frequent than that with quartz ; but, as 

 these different earthy minerals frequently occur together, and 

 particularly quartz and calcareous spar, it is not necessary to 

 distinguish the metallic ones that seem to be in some cases 

 peculiarly associated either with the one or with the other. 

 The following list, therefore, contains those which are found in 

 these associations, arranged according to their chemical natures, 

 and under the most general terms. 



Metals and Alloys. 



Gold. Bismuth. 



Silver. Tellurium. 



Arsenical silver. Mercury and silver; (amalgam.) 



Iron. Antimony. 



Copper. Arsenical iron ; (pyrites). 



Arsenical Cobalt ; (white cobalt). Arsenical nickel (kupfer nickel). 



OXYDES. 



Ccpper ; black and red. Arsenical oxyde. 



Iron ; oxydulous. Hematite. Uranium ; green and black. 



Lead ; minium. Manganese ; red and black. 



Titanium ; rutilc, anatasc. Cobalt ; red and black. 



Salts. 



Silver ; muriat. Tungsten ; wolfram. 



Copper ;muriat,arseniat,phos- Zinc, carbonats. 



phat. Bismuth ; carbonat. 



Lead; phosphat,carboiiat, sul- Titanium; siiicat. (Sphenc). 



■ phat, molybdat. 



Iron ; muriat, arseniat, carbo- 

 nat, phosphat. 



