RARE METALS AND THEIR DISTRIBUTION. 
83 
The Rare Metals and their Distribution in 
Western Australia, By Edward S. Simpson, B E., 
F.C.S., being the Anniversary Address of the 
President, Session 1911-12. (Delivered J une 11th, 
1912.) 
Plate XVIII. 
Introduction 
General Distribution ol the Rare Metals.. 
The Rare Metals in Western Australia : — 
Lithium 
Caesium and Rubidium 
Beryllium 
Cadmium 
Gallium, Indium, Thallium 
Yttrium Group of Metals 
Cerium Group of Metals 
Thorium 
Zirconium 
Germanium 
Vanadium 
Tantalum and Niobium 
Molybdenum 
Uranium and Radium 
Platinum and the Platinoid Metals . . 
83 
86 
87 
90 
90 
9 1 
9 1 
92 
94 
96 
96 
98 
98 
100 
104 
105 
107 
Introduction. 
What does the term “Rare Metal ” mean ? It is a 
term frequently employed, yet no authoritative and satis- 
factory definition is to be obtained. Further, cases are not 
infrequent where a “ rare metal ’’ of one generation becomes 
a common or moderately common metal of the next. What 
then is a practical criterion of a “ rare metal ’’ ? 
The latest (1912) international list of elements contains 
no less than Pi metals out of a total of 82 elements, yet of 
these 61 how few are really common metals. Perhaps if 
we seek first to define a common metal we may then con- 
sider all those which do not come under this category as 
coming under the complementary one of “ rare metals.” 
Let us then tentatively define a common metal as one 
which forms a quite appreciable proportion of the whole 
earth’s crust, say at least one part in 1,000. According to 
Clarke* there are only seven such, viz. : — - 
Aluminium 
Iron 
Calcium . . 
Magnesium 
Sodium . . 
Potassium 
Titanium . 
7.34 per cent. 
4-n 
3-iQ 
2.24 
2-33 
2.28 
0-37 
* F. W. Clarke : Data of Geochemistry. 
