Vol. 60.] OF THE GOLD-DEPOSITS OF BAEKERVILLE. 393 



At the time when Daintree died, a few years later, no results could 

 be discovered: hut one of the bottles was removed to Dr. Percv's 

 private laboratory, and there in 1886, or 15 years after the 

 commencement of the experiment, a cluster of minute crystals 

 of gold was discovered upon the smooth surface of the iron- 

 pyrites. 



In the case of the Xew Guston and adjacent mines in Colorado, 

 with which the speaker was connected some 12 years ago, the ore- 

 occurrence presented at that time many points of great obscurity, 

 but, as since pointed out by Emmons, Richard, and others, if the 

 theory of secondary or zonal enrichment were applied, these diffi- 

 culties largely disappeared. As regarded the Xew Guston mine — 

 galena was most abundant from the surface down, say, to 300 feet, 

 the ore carrying S to 50 per cent, of lead, 9 to 30 ounces of silver 

 with a trace of gold. At a depth of about ISO feet copper-pyrites 

 with stromeyerite came in, and continued down to about 700 feet, 

 the assays being : copper 5 to 15 per cent., '25 to 700 ounces of silver, 

 one-tenth to 3 ounces of gold. At about 600 feet soHd bodies of iron- 

 pyrites were discovered, which continued to the deeper workings, 

 carrying 1 to 3 per cent, of copper, 4 to 20 ounces of silver, and two- 

 tenths of an ounce of gold. Bornite was met with between 700 

 and 1200 feet, carrying 18 to 25 per cent, of copper. 60 to 175 ounces 

 of silver, and a quarter to 11 ounces of gold. Free gold, which 

 was never seen above the 700-foot level or in any other instance, 

 was found associated with the bornite below the 700-foot level. 

 The workings were suspended at about 1500 feet. 



With reference to the previous speakers remark, it might be 

 stated that calcite was not unknown as a matrix of gold : and 

 A. G. Lock had stated that most of the rich quartz-reefs at Gympie 

 (Queensland) contained abundance of calcite in strong veins and 

 patches, often richly impregnated with gold. A fine specimen from 

 these showed actual veins of fairly-large gold specks, irregularly 

 distributed through white opaque calcite. 



