9 8 
EDWARD S. SIMPSON, B.E., F.C.S. : 
From this analysis and from microscopical examination 
the following mineral composition has been calculated : — 
Zircon about 71% 
Rutile 11 
Ilmenite 12 
Cassiterite 3 
Monazite 1 
Cyanite traces 
Gahnite 
Magnetite ,, 
Apatite ,, 
Germanium — This very rare metal was first recognised 
in 1886 by Winkler, and has since been prepared in 
metallic form in light grey lustrous crystals. It is an 
essential constituent of one mineral, argyrodite, a sulphide 
of silver and germanium. Small proportions occur in Can- 
fieldite, another silver ore, whilst traces have been detected 
in Euxenite and other tantalum minerals. 
Our present interest in this metal lies in th.e fact that, 
according to my friend Mr. W. B. Giles, F.I.C., a chemist 
with considerable experience of the rare metals, germanium 
occurs in quite appreciable quantities in the Stibiotantalite 
from Greenbushes. 
Vanadium —Vanadium, first discovered in Mexican 
ores by del Rio in 1801, is one of the few rare 
metals the presence of which in rocks or minerals 
in as small proportion as one part in ten thousand 
can readily be detected with the help of the simplest 
apparatus. Largely because of this fact it is known 
to be widespread in small quantities. Clarke* estimates 
that it forms about one part in every five thousand 
of the whole earth’s crust, but this figure is a rough ap- 
proximation only. In addition to this wide distribution 
in small quantities in most rock masses, the metal is con- 
centrated in larger proportion in certain characteristic 
minerals which form the source of the world’s supply of 
the metal and its compounds. The most important of these 
minerals are Carnotite (vanadate and uranate of potash) 
and Vanadinite (chlorovanadate of lead). Other less com- 
mon minerals are Roscoelite, a vanadium mica, and Pucher- 
ite, a vanadate of bismuth, both of which are recorded from 
Western Australia. 
The chief commercial use for vanadium is an addition 
in small amounts to steel for certain purposes, particularly 
springs, saws, motor car parts, etc. Several compounds are 
used in small quantities. 
* Data of Geochemistry. 
