Looking into more sources.  What are the implications for a furnace that is
using an ore with the following:

Fe 47-52%    SiO2 11%    TiO2 6.5%    Manganese present Phosphorus 0.055%

Minerals include: Magnetite, Ilmenite, Apatite, Biotite, Grunerite, Hornblende,
Zircon, and Garnet

They are using a local limestone as flux and charcoal as fuel.

Forsythe 1922 based on work of AJ Rossi (The Blast Furnace and the Manufacture
of Pig Iron) p182

"titanites are not infusible but that in slags having about 60 per cent of acid
constituents, as much as 35 per cent TiO2 was substituted for SiO2 without
decreasing the fusibility of the slag."

William Bowron The Practical Metalurgy of Titaniferous Ores in Trans of Amer
Inst of Mining Engineers, vol 11 (1883).  Based on operations at Norwegian
Titanic Iron Co and

"...a perfect success; but the enormous quantity of fuel required,... militated
seriously against its commerical success..."

"perofskite, the titanite of lime found in nature, is practically infusible,
while the silico-titanite of lime is fairly fusible.  A study of minerals seems
to point to the fact that those that contain titanic acid and magnesia together
in quantity are usually refractory and infusible."

""secret of working these ores successfully and continuously is to keep the heat
so low as just to reduce the iron and not reduce the titanic acid.  The iron
will be white, or, at best mottled, if there is much titanic acid to contend
with.  Titanic iron is essentially a forge iron.  Foundry iron can only be
produced when the titanium is low, and then only by making a large quantity of
cinder, so as to "wash" the titanic acid out of the furncae.  This, of course,
is at the expense of fuel, and the tendency to obstruct the hearth is
intensified....  If from any cause the furnace reduced the titanic acid, and is
in a choked condition, the readiest modes of relief consist in throwing off the
ore that caused the trouble, substituting a non-titaniferous ore,... and raising
the heat."

David Forbes article in Chemical News, 11DEC 1868.  Fuel consumption was about
20% higher and pig production was cut in half.

"The only objection to the use of titaniferous ore is that they are found to be
more and more refractory in the furnace in proportion as they contain a larger
proportion of titanic acid; and if much titanium is present they require so much
larger an amount of charcoal to smelt them as not to render their employment
profitable..."

"examination of some silico-titanites, which proved more fusible than pure
titanites, led me to employ a mixture of limestone and stamped quartz as a
flux.  This was found satisfactory ..when the amount of titanium did not exceed
8%..."




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