ft-.^rTfl^"- J^. L T ? 



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366 



K&SUME AND THEORETICAL DISCUSSION. 









s 



Platinum 



Iridium 



Rhodium 



Palladium 



Gold 



Copper 



Iron 



Osmiuret of iridium 



Sand 



Lead 



Osmium and loss 



I 



85.50 



1.05 

 1.00 

 .60 

 .80 

 1.40 

 6.75 

 1.10 

 2.95 



II 



79.85 



4.20 



0.65 



1.95 



.55 



.75 

 4.45 

 4.95 

 2.60 



101.15 



0.05 

 100.00 



III 

 76.50 



0.85 



1.95 



1.30 



1.20 



1.25 



6.10 



7.55 



1.50 



0.55 



1.25 



100.00 







r 









Of other metals, the following have come under our notice as occurring 

 in gold washings from California and the Pacific Coast region generally : 

 copper, le?od, iron, and nickel. Grains of native copper have repeatedly been 

 noticed by the writer, and these were undoubtedly genuine. Small particles 

 of lead were detected by Mr. Wadsworth in three specimens of gold washings 

 from Rock Creek, Morris Ravine, and near Placerville.* He is unable to 

 decide whether they are or are not really native metal. Small fragments of 







metallic iron, also observed in some of Professor Pettee's specimens, have 

 almost certainly been introduced into the washings by accident. 



The occurrence of native nickel, however, is one which is unquestionably 

 authentic, and is due to Mr. J. A. Edman, by whom specimens have been 

 presented to the w T riter. The locality is Trinity Bar, five miles below Fort 

 Yale, on Fraser River. The nickel is in the form of minute rounded grains, 

 associated with magnetite, garnet, gold, platinum, and (probably) iridosmine. 

 Dr. Gibbs examined the nickel grains, at the request of the writer, and 

 reported that they were nearly pure nickel, containing traces of iron and 

 cobalt. This is an extremely interesting discovery, as being the first well- , 

 authenticated instance of the occurrence of native nickel.f 



Gems of beauty or value are, with the exception of the diamond, rarely if 

 ever found in the gold washings. Garnet is somewhat frequent, and is often 

 mistaken for ruby. Topaz has been reported, and crystals supposed to be of 



* 



* The surface of the lead is much pitted, corroded, and coated with a whitish earthy substance (rb C0 8 ?), and 

 the grains are very irregular in form. 



t The metallic iron found in the basaltic rocks of Greenland, at Ovifak, contains a little over two per cent of 

 nickel. The question whether this iron is of meteoric or terrestrial origin has been considerably debated without 

 a positive decision having been reached. The weight of evidence, as the writer believes, is strongly in favor of 

 their having come from below rather than from above. 





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