Auriferoux Sandstones of Chiltern. 289 



As these sandstone pebbles cai-rying <folcl are not derived from 

 beds of auriferous sandstone, tlie quest for the latter can be 

 dropped ; but the facts disclosed bear very distinctly on the 

 problems of the enrichment and impoverishment of auriferous 

 lodes above water level, also on the presence of gold in solution 

 in the waters of alluvial leads. 



In the early days of quartz mining in this 8tate it was a 

 common circumstance to find at and near the surface that the 

 joints and faces of the quartz were coated with extremely thin 

 films of gold. 8uch tilms were no doubt formed from solutions 

 tliat had previously dissolved some of the gold out of the adjacent 

 stone. The term "New Chum Gold" was applied to such 

 occurrences, because inexperienced miners were apt to over- 

 estimate the value of such finds. Paint-gold was another name 

 applied to such occurrences. 



In most auriferous quartz lodes the ore above permanent 

 water level differs entirely in nature from that below water 

 level. Below water level the ore is as originally formed, and 

 consists of quartz and other gaugue and metallic minerals in the 

 foi m of sulphides, except the gold, which is in metallic form, the 

 so called refractory ores. Such ores ai'e due to deposition from 

 the lower circulating waters, which have brought them up from 

 deeper levels. 



Above the permanent water lines the ores met with have 

 resulted from the de-sulphurising and oxidising of these sulphide 

 ores, through the agency of rain and air, which obtain access to 

 the lode-material. 



To the upper zone of auriferous lodes the term "zone of 

 enrichment " has been applied in many cases. This is an apt 

 definition, for enrichment of the surface and to shallow depths of 

 such lodes has frequently taken i)lace, and in one of the following 

 ways : — 



First. — Mechanically, where the cruml)ling away of the gold 

 matrix has set the metal free and allowed it to drop near the 

 ontci'op of the lode. Innumerable exanq)les of such enrichments 

 near the cap of the lode were met with in Victoria, in all the 

 Australian States, and in South Africa. 



Phenomenal yields weie connnon in Victoria at and near the 

 outcrop, and for a short distance down, or as far as the quartz 



