120 



is oxidized and transformed into hydrated oxide of iron, and 

 the gold is set free in a finely divided state ; bnt the particles 

 of gold at the moment of liberation seem to have the property 

 of welding together to form grains or nuggets. Pseudemorphs 

 of brown hiematite after iron pyrites are common objects in 

 the upper parts of the majority of our auriferous veins, from 

 which may be inferred the existence of iron pyrites at lower 

 depths. In consequence of the process to which I have just 

 referred, the quantity of free gold in a reef will diminish with 

 the increase of depth from the surface. But disintegrating 

 agents are constantly reducing the virgin matrix of the reef to 

 a gossan or mullocl^ through which some quantity of the 

 liberated gold works its downward course, beyond the reach 

 of the denuding agents w^hich are reducing the absolute height 

 of the reef, concurrently with the formation of gossan in depth. 

 Under these circumstances the quantity of free gold is con- 

 stantly accumulating in the gossan. The knowledge of this 

 fact, as also that of the distribution of gold in horizontal extent, 

 may be profitably applied to the mode of preliminary exploita- 

 tion of a reef. The common method is to sink a shaft through 

 barren ground to intersect the reef at a certain depth, by which 

 the existence of the vein is proved and its auriferous character 

 determined at that depth ; whereas the same sum of money 

 spent in opening on the vein would serve the first object 

 equally well, whilst from the vastly large extent of vein that 

 is brought under examination a more reliable estimate of its 

 auriferous value can be formed, and no dead labour is entailed, 

 that is if the veinstone contain a payable quantity of gold. 



I cannot refrain from adding, by way of concluding this 

 section of my address, some remarks which, though beyond the 

 scope of my subject, are yet worthy of consideration as affect- 

 ing the prosperity of our gold-mining industry. I sincerely 

 hope that we have entered on a new phase of gold mining, so to 

 work our gold mines as to yield profit. Let but one of the many 

 ventures now before the public prove a success — and I am very 

 hoj)eful in respect to some of those on the "Waukaringa lode — 

 I do not doubt but that other mines will be similarly so 

 energetically developed as to prove prosperous. Hitherto the 

 value of our gold reefs has never been fairly tested. The 

 want of success is to be sought rather in methods pursued than 

 on account of the percentage yield of gold A mine to be pros- 

 perous must be under skilled management, and the working 

 expenses must be on a liberal scale. One held by a proprietary 

 has a better chance of success than one worked by a Company, 

 for several reasons ; but a prominent one is that in the former 

 the good business principle is acted on of making the mine 

 provide for its own development. 



