34 THE ROYAL SOCIETY OF CANADA 
separation between the iron and the titanium as the iron minerals are 
more magnetic than those of titanium, but the iron and titanium 
minerals are too closely associated to permit of a perfect separation. 
Magnetic concentration would in general be used to enrich titaniferous 
iron ores as far as practicable before submitting them to the smelting 
operation. 
Titanium in an ore is not objected to as lowering the quality of the 
resulting pig iron, as it is admitted that the iron produced from titani- 
ferous ores is frequently of a very high quality, but such ores are more 
difficult and costly to smelt and it has been supposed that an ore con- 
taining so little as one per cent of titanium would be almost impossible 
to smelt in the blast furnace. It should also be remembered that 
magnetites, even when free from titanium are not so easily smelted 
as hematites, and that blast furnace managers prefer to import the 
easily smelted American hematites instead of using the Canadian 
magnetites, partly because they do not understand the correct treat- 
ment of magnetites. 
Until quite recently the situation with regard to the smelting of 
titaniferous ores was substantially as follows: 
(1) Fifty or sixty years ago titaniferous ores were smelted without 
serious difficulty in the small charcoal furnaces then in use. 
(2) It has generally been supposed, in more recent practice, that 
titaniferous ores are very difficult if not impossible to smelt; so little 
as one per cent of titanium being sufficient to make an ore infusible 
in the blast furnace. It was supposed that titanium makes the slags 
sticky and further that it forms infusible accummulations of cyano- 
nitride of titanium, which eventually choke the furnace. 
(3) A. J. Rossi has, for a number of years, advocated the use of 
titaniferous ores; stating that they are in no way more difficult to 
smelt than other ores, providing that the titanium is properly fluxed. 
He states that titanium oxide, TiOs, in an iron ore should be regarded 
as equivalent to an equal amount of silica, and sufficient limestone 
provided to flux it; dolomite, moreover, being found to serve better 
than limestone as a flux. 
In view of these contradictory views much doubt has prevailed. 
The positive statements of Rossi have greater weight than the vague 
prejudice against the use of such ores, but there has been a feeling that 
Rossi might be biassed in his views and that there must be some foun- 
dation for so widespread a prejudice. 
It should be explained that ordinary iron ores contain an oxide 
of iron, with silica, alumina, etc., and that limestone is added as a flux. 
The oxide of iron is reduced to the metallic state almost completely 
while the oxides of aluminium and of calcium remain unreduced. 
