The Breadalbane Mines. 201 



deposited the most metalliferous minerals. What the 

 chemical process was, is a much more difficult question, and 

 how it has come about that there is at some places a mineral 

 vein, and at others nothing but a barren quartz reef, is a 

 problem to which the data at Tyndrum are insufficient to 

 afford a solution. 



IT. — CORRYCHARMAIG. 



At this locality, three miles from the foot of Glen Lochay, 

 which joins the valley of the Dochart at Killin, chrome iron 

 ore was mined on a limited scale by the late Marquis of 

 Breadalbane. 



The workings consist of one small drift, now standing full 

 of water, and several small open pits above. The ore is 

 found on the south side of the glen in a mass of serpentine 

 about half a mile in extent from east to west and three 

 hundred yards in breadth. At the top of the hill the rock 

 is tough and green, but is soft and white in the drift below. 

 The mass of serpentine has an apparently bedded structure, 

 with a W. 20° S. dip, at an average angle of 30°. As the 

 dip of the mica schists on the hill above and below varies 

 from S. to S. 20° W., the serpentine may possibly be inter- 

 calated between their bedding planes. The surrounding mica 

 schists are generally garnetiferous, and in some cases con- 

 tain small bands of serpentine. The chrome iron ore appears 

 to be disseminated through the serpentine in detached grains 

 or aggregates, and no vein is to be seen. It occurs in masses, 

 sometimes angular, but more often reniform or lenticular in 

 shape, and varying in size from that of a pea to blocks 5, 10, 

 and, in one instance, as much as 30 tons in weight. Small 

 cavities lined with minute octahedral crystals of the ore are 

 not uncommon. The minerals associated with it are actino- 

 lite, steatite, crysotile, and magnetic and copper pyrites. 

 From the trial workings made over this field, about 60 tons 

 of ore were raised and sold in 1855-56, but the ground is 

 still practically unproved. The following analysis was made 

 by W. Valentine in 1862 : 



Sesquioxide of Chrommm, 36*86 per cent. = Chromic Acid, 48 "3 per cent. 

 Protoxide of Iron, . 20 '27 per cent. 



