18G5.] Hunt on British Gold. 641 



and it is a fact deserving of note, that away from the vicinity of those 

 rocks, no good gold lode has been discovered. 



The most important gold mines in North Wales are the Vigra and 

 Clogau, from which, as we stated in our Chronicles of Mining in our 

 July number, 10,778 ounces of gold had been obtained to the end of 

 1864. For some years, both the Vigra and the Clogau mines were 

 worked for copper. They are now united as auriferous quartz mines, 

 but nearly all, if not all the gold, has been obtained from the latter. 



The Clogau St. David, No. 1 mine, is certainly the richest gold 

 mine ever worked in the British Islands, and may compare favourably 

 with the quartz reef mines of Australia. According to Mr. Dean, 

 from a space of ground not more than fifty fathoms long by thirty 

 fathoms deep, and only a portion of which has been worked away, 

 there had been extracted at the 31st of May last, and reduced 4,154 

 tons of quartz, yielding 11,508 ounces of gold, giving an average of 

 2 oz. 15 dwts. 19 grs. jDer ton. Taking this lode as a type of those 

 which occur in its neighbourhood, it will be well to describe it. 



The lode has an average bearing 15° N.E., and is intersected by a 

 very powerful cross-course, bearing 30° N.W., and dipping slightly 

 S.W. The lode traverses beds of indurated Silurian clay slate, which 

 are interstratified with thick beds of greenstone. There is also a 

 large greenstone dyke, which is traversed by a portion of the lode for 

 a length of about sixty fathoms, until they are intersected by a great 

 cross-course. Behind this cross-course the lode is extremely rich in 

 gold. It should be stated that the lode is composed almost entirely 

 of quartz, with here and there some carbonate of lime. Throughout 

 the quartz, yellow copper ore is, in small quantities, disseminated as 

 well as gold. Where the gold is most abundant, Telluric Bismuth in 

 fine silvery white grains is generally present, and an opinion prevails 

 that whenever that mineral is met with, gold is near at hand. It was 

 commonly supposed that gold is only to be found near the surface. 

 Mr. A. Dean has favoured us with some notes on this point, which 

 are exceedingly important if all the conditions have been correctly 

 observed. Without comment, Mr. Dean's own words are given : — 



" The opaque white quartz floors, which are comparatively poor in gold, 

 alternate with others of a greenish white colour, very dense, and of a shining 

 conchoidal fracture ; the latter are the rich gold-bearing floors ; we have, 

 therefore, alternate rich and poor floors. From the dip of the floors the 

 deposits of gold appear individually to dip eastward, but, as the bands of 

 clay-slate forming the walls of the lode below the greenstone dip westward 

 down to the cross-course, the succession of bunches of gold in the 

 alternate floors of greenish quartz follow the dip of the clay-slate. This 

 is an important point in relation to the recurrence of rich deposits of 

 gold in depth below the present bottom." 



This quotation sufficiently indicates the hypothesis that with a 

 recurrence of the same conditions in depth, rich, or perhaps richer, 

 deposits of gold may be met with. There is a very close analogy 

 between gold and tin. It was an opinion, held with much obstinacy 

 for a long period, that tin would never be found deep in the earth. 

 Experience has now proved the fallacy of this, for the most abundant 



