332 A. LIVERSIDGE. 
quartz associated with gold certainly originates from the decom- 
position of silicates in rocks, and it may be conjectured that the 
gold has the same origin, possibly existing as silicates.” 
I have verified Bischof’s statement by digesting gold leaf with 
sodium silicate and potassium silicate solutions under a pressure 
of ninety pounds to the square inch, and found that the solution 
gave a brown precipitate with oxalic acid, and that this acquired 
the metallic lustre and colour of gold under a burnisher. 
The reduction of gold chloride in solutions of sodium and 
potassium silicates, also mentioned by Bischof, was verified, but 
I do not attach much importance to these experiments, for gold 
chloride is so easily reduced that its reduction is brought about 
by almost anything; the fact that gold is dissolved by sodium 
silicate is a matter of much greater importance. The solution in 
sodium silicate turned blue in about thirty minutes, that in 
potassium silicate took a longer time, and the separated gold 
was of a reddish tint. 
J. Cosmo Newbery states that an amethystine colour is some- 
times seen in quartz reefs and in wash dirt. Aplin, at Beechworth, 
Victoria, found that such clay, after exposure to light, lost its 
colour and showed the presence of gold although none was visible 
before ; a successful miner, Clement, observed the same thing at 
Maldon. This appears to indicate that the clay was moistened 
with a solution of a gold salt. No chemical examination was, 
however, made. 
Lock (p. 558) quoting from Prof. Hutton On the Thames Gold 
Field, says: ‘‘Of the time when the veins were first charged with 
gold, Hutton can offer no opinion ; but there are one or two facts 
which make it appear probable that gold is still in circulation 
throweh*the rocks.) M7 24 3s In the Niau claim, above the 
Hokianga, on the Karaka, open quartz veins are seen partly filled 
with black humus that has filtered down from the vegetable soil 
above and this humus, on being carefully washed, yields fine gold, 
which Hutton supposes had been precipitated from solution by 
the organic matter of the humus.” 
