11 
4. The frequent presence of secondary potash minerals, 
chiefly muscovite, in auriferous metasoinatic lodes, 
this potash being largely in excess of that in the 
original rock : 
5. The frequent enrichment of gold veins, e.g. } at Lennon- 
ville, at the intersections with previously existing 
bands of haematite (ferric oxide), a moderately 
strong oxidising agent : 
0. The occasional intimate association of gold with other 
strongly oxidising agents, for example, with man- 
ganese dioxide at Kanowna, and with chromium 
compounds at Westonia. 
These six conditions associated with enhanced gold precipi- 
tation do not appear to be compatible with the theory of the in- 
troduction of gold in the form of solutions of auric chloride and 
auric cation, whilst they are intelligible with the theory of the 
introduction of gold in magmatic waters carrying potassium sul- 
phaurate and free sulphaurate anion. 
The purely chemical aspect of the genesis of gold in our primary 
gold deposits is one which is in urgent need of investigation, and 1 
think you w r ill agree with me that the solution of this problem 
cannot but have a very important bearing upon the prospecting 
and exploiting of such deposits both in Western Australia and 
elsewhere. 
In quite a different direction altogether the mineral chemist 
is destined to play a large part in the near future. Up till now, 
thanks to nature’s industry, we have been enabled to obtain suffi- 
ciently large supplies for our necessities of such minerals as are 
usually adapted to manufacturing processes, in consequence, a 
very superficial and incomplete knowledge of the chemistry of 
minerals has enabled us to keep the w r orlcl supplied with all its 
needs of soluble potash and phosphorus salts, of metallic aluminium, 
copper and iron, and so on. The war has already proved to us the 
grave danger of relying too completely upon a single source of any 
essential mineral product, and the rapid exhaustion of high grade 
crude minerals all the w orld over w ill compel us to a closer chemical 
study of the lower grade minerals upon which we are destined to 
become more and more dependent. 
As an example of what scientific assistance can be given in 
this direction let us consider the position in relation to potash 
supplies created by the war. The Germans have been favoured 
by Nature w T ith an immense supply of high grade and easily treated 
potash minerals. Because of this they had by 1914 monopolised 
the w r hole potash supply of the world. The cutting off of this 
supply created a potash famine in Australia, affecting many in- 
dustries but particularly fruit and potato growing. To relieve 
