actual work of prospecting. What the prospector
requires to know is, first, the usual locality of occurrence of the more
valuable minerals; secondly, their appearance; thirdly, a simple mode
of testing. With respect to occurrence, the older sandy and clay slates,
chlorite slates, micaceous, and hornblendic schists, particularly at or
near their junction with the intrusive granite and diorite, generally
form the most likely geological country for the finding of mineral
lodes, particularly gold, silver and tin. But those who have been
engaged in practical mining for long, finding by experience that no two
mineral fields are exactly alike in all their characteristics, have come
to the conclusion that it is unwise to form theories as to why metals
should or should not be found in certain enclosing rocks or matrices.
Some of the best reef gold got in Victoria has been obtained in dead
white, milky-looking quartz almost destitute of base metal. In South
Australia reef gold is almost invariably associated with iron, either
as oxide, as "gossan;" or ferruginous calcite, "limonite;" or granular
silica, conglomerated by iron, the "ironstone" which forms the capping
or outcrop of many of our reefs, and which is often rich in gold.

But to show that it is unsafe to decide off-hand in what class of matrix
metals will or will not be found, I may say that in my own experience I
have seen payable gold in the following materials:--

Quartz, dense and milky, also in quartz of nearly every colour and
appearance, saccharoidal, crystalline, nay, even in clear glass-like
six-sided prismatic crystals, and associated with silver, copper, lead,
arsenic, iron as sulphide, oxide, carbonate, and tungstate, antimony,
bismuth, nickel, zinc, lead, and other metals in one form or another;
in slate, quartzite, mica schist, granite, diorite, porphyry, felsite,
calcite, dolomite, common carbonate of iron, siliceous sinter from a hot
spring, as at Mount Morgan; as alluvial gold in drifts formed of almost
all these materials; and once, perhaps the most curious matrix of all,
a small piece of apparently alluvial gold, naturally imbedded in a shaly
piece of coal. This specimen, I think, is in the Sydney Museum. One
thing, however, the prospector may make sure of: he will always find
gold more or less intimately associated with silica (Quartz) in one or
other of its many forms, just as he will always find cassiterite (oxide
of tin) in the neighbourhood of gr