408 S. RADCLIFF. 
ON THE RECOVERY OF ACTINIUM AND IONIUM 
FROM THE OLARY ORES. | 
By 8S. RADCLIFF. 
[Read before the Royal Society of N.S. Wales, November 4, 1914.) 
A general account of the methods devised for extracting 
radium from the interesting ore complex occurring at Olary, 
South Australia, has already been given,* the present com- 
munication deals with the recovery of the ionium and 
actinium. Both ionium and actinium possess many of the 
properties of the rare earths, and separate out along with 
these in the course of treatment. It is necessary, there- 
fore, to investigate the distribution of the rare earths in 
the various residues and precipitates produced in treating 
the ore, and to examine these chemically and also by means 
of the electroscope. 
ITonium. 
As ionium appears to be chemically inseparable from 
thorium, the activity of the ionium preparation that can 
be separated from a given ore depends on the ratio of the 
uranium to the thorium in it. 
The chemistry of thorium has been very fully worked 
out, and in order to obtain an active ionium preparation 
from an ore, all that is necessary is to extract the thorium 
and purify it by any of the well known methods. The 
uranium thorium ratio for the Olary ore is about 100: 1. 
It is possible therefore to obtain from it ionium prepara- 
tions of considerable activity. 
Actinium. 
Our knowledge of the chemistry of actinium is very 
imperfect, none of its salts have yet been prepared in a 
* Proc. Roy. Soc. N.S.W., XLVIIL, p. 146. 
