On a Specimen of Native Copper. 133 



But Ludwig Becker obtained a specimen of metallic zinc 

 from a cavity in tlie basalt at Brunswick (near Melbourne) ; 

 doubts were expressed at the time concerning the genuine- 

 ness of this discovery ; in one of the English scientific 

 journals it was compared to the spurious nuggets stated as 

 being so commonly manufactured on the Australian goldfields. 

 There are no doubt many among our visitors now present 

 to whom Becker was personally known, and who have a 

 vivid recollection of his zeal and attainments ; I believe it is 

 needless to speak of personal reliability ; but I may be 

 permitted to add that I had opportunity of examining his 

 specimen, and that its hackled fracture, its crust with a 

 peach-blossom tint, and indeed its characters generally, left 

 no doubt on my mind of its being; a mineral, intact and in 

 its native state — a new mineral species. 



Admitting these examples as showing that native metals 

 do occasionally occur in basaltic rocks, then we arrive at the 

 particular question, namely, does native copper ever occur 

 under such conditions ? The answer to this is, that copper 

 mines pertaining to trap formations appear to have been 

 worked from the time when the Phoenicians traded 

 with Cornwall for tin, and that such deposits of 

 native copper are worked at the present day. At 

 Lake Superior, native copper, thus geologically related, 

 is found in masses of what would seem as almost a fabulous 

 weight. Dr. Daniel Wilson, in his work, " Prehistoric 

 Man," states, that in the veins of the copper regions of Lake 

 Superior, the native metal occurs in enormous masses 

 weighing hundreds of tons, and many loose blocks of con- 

 siderable size have been found on the lake-shore, or lying 

 detached on the surface. He describes a visit to these 

 mines, and speaks of passing in some cases literally through 

 tunnels made in the solid copper. He describes the floors 

 of the levels strewed with the copper shavings struck off 

 in the effort to detach blocks of the metal from the solid 

 vein, and in cutting them clown to dimensions sufficiently 

 small for transport. One mass of copper quarried from the 

 cliff mine has been estimated to weigh eighty tons. It was 

 sufficiently detached from its rocky matrix, without injur- 

 ing its original formation, to admit of its dimensions being 

 obtained with considerable accuracy, and it was found to 

 measure fifty feet long, six feet deep, with an average of 

 about six inches of thickness — a wall of solid copper. 

 In London, thirty years since, I myself saw a mass of 



