1865. J Mining, Mineralogy, and Metallurgy. 115 



Near the Fitzroy Iron Mines a seam of coal thirty-eight feet in 

 thickness has been discovered. This will, after making every allow- 

 ance for waste, yield 30,000 tons an acre. At Illawarra a stratum of 

 clay band iron-stone has been found, and shortly at Fitzroy the first 

 Australian blast-furnace will commence operations with native ma- 

 terial. 



Amongst the Foreign mines, which greatly influence the English 

 market, those of Chili are the most important. Recent returns of 

 the produce of that country in the years 1861 and 1862, show the 

 value of the minerals exported to this country — 



1861. 1862. 



Cobalt ore £17,980 



Copper ore 430,523 



„ Regulus .... 736,290 



„ Uirwrought . . . 275,555 



„ Part wrought . . . 22S,38S 



Nitre, cubic 26,133 



Silver ore 269,747 



£4,660 



465,192 



1,211,340 



204,421 



302,965 



39,131 

 285,348 



The following interesting notes on the new Almaden Quicksilver 

 Mines are from the pen of B. Silliman, junior, of San Francisco : — 



" The new Almaden Quicksilver Mines are situated on a range of 

 hills subordinate to the main coast range, the highest point of which 

 at the place is 1,200 to 1,500 feet above the valley of San Jose. South- 

 west of the range which contains the quicksilver mines, the coast- 

 range attains a considerable elevation, Mount Bache, its highest 

 point, being over 3,800 feet in height. 



" The rocks forming the range in which the quicksilver occurs 

 are chiefly magnesian schists, sometimes calcareous and rarely 

 argillaceous. In geological age, they are probably not older than 

 cretaceous. There is no such thing as a well-characterized vein of 

 ore, the quartz and its associated metals occurring rather in isolated 

 masses or bunches segregated out of the general mass of the meta- 

 morphic rocks, and connected with each other, somewhat obscurely, by 

 thread veins of the same mineral. The principal minerals associated 

 with the cinnabar are quartz and calcareous spar, which usually occur 

 together in sheets or strings, and in a majority of cases penetrate or 

 subdivide the masses of cinnabar. Sometimes narrow threads of these 

 minerals, accompanied by a minute coloration of cinnabar, serve as 

 the only guide to the miner in re-discovering the metal when it has 

 been lost in a former working. 



" The main entrance to these mines, at present, is by a level about 

 800 feet long, and large enough to accommodate a full-sized railroad 

 and cars. This level enters the hill about 300 feet from its summit, 

 and is driven into a large chamber, formed by the removal of a large 

 mass of cinnabar, leaving ample space for the hoisting and ventilating 

 apparatus employed in working the mine. At this point a vertical 

 shaft descends to an additional depth of nearly 300 feet, over which is 

 placed a steam ' whim,' by means of which the ore from the various 

 workings is conveniently discharged into the cars which convey it out 

 of the level to the dressing-floors. In order to reach the lower work- 



i2 



