14 
IRON ORE DEPOSITS' NEAR MIRBOO NORTH, 
SOUTHERN GIPPSLAND. 
(no. io on locality map.) 
By Professor J. W. Gregory , D.Sc., F.R.S. , &*c. t late Director , 
Geological Survey of Victoria. 
Recently I visited Mirboo North, and examined the iron ore deposits 
found near there. 
The Ore. 
A sample of the ore was recently analyzed at the Mines Department 
Laboratory, and Mr. P. G. W. Bavly reported its composition as fol¬ 
lows:— 
Per cent. 
Silica ... ... ... ... 2.75 
Titanic oxide ... ... ... ... 1.00 
Ferric oxide ... ... ... ... 77.14 
Ferrous oxide ... ... ... ... 1.80 
Alumina ... ... ... ... 3.70 
Lime ... ... ... ... nil 
Magnesia ... ... ... ... nil 
Sulphur ... ... ... ... .07 
Phosphorus ... ... ... ... .01 
Water (at 100 deg. C.) ... ... ... 2.22 
Water (ignition) ... ... ... ... 11.30 
99.99 
This analysis is very favorable, as it closely agrees with the standard 
of American Bessemer ores, and is indeed slightly better than the average 
of them, being lower in phosphorus. The American standard for Besse¬ 
mer ore is: — 
Per cent. 
I r on ... ... ... ... 63 
Water ... ... ... ... 10 
Phosphorus ... ... ... ... .045 
General Geology of the Area. 
The ore deposit may, therefore, be regarded as including excellent 
material, but its value depends on the quantity, and -the chances of its 
successful exploitation. The deposit occurs in the allotment of Mr. H. 
J. Funston, No. 98, parish of Allambee East, three miles, in a straight 
line, N. 7 deg. W. of Mirboo North. It is a little to the east of 
Lydiard’s track, at the approximate height of 1,200 feet above sea level. 
The geology of this area is somewhat complex, the various rocks 
having been disturbed by a series of powerful faults; and the task of un¬ 
ravelling the knot into which these disturbances have tied the beds is 
rendered difficult by the thick cover of forest. The foundation of this 
district is the thick mass of Jurassic sandstones, known as the Victorian 
Coal Measures, because in some districts of Victoria they enclose coal 
seams. Above the sandstones is a series of much more recent deposits, 
including some quartzites, clays, and brown coals; above them occur in 
places, sheets of basalt and volcanic deposits, now mostly decomposed; 
and above this formation is a still later series of deposits, 
including gravels, sands and ironstone conglomerates, and, most notice¬ 
able of all, are thick beds of mottled, many-coloured clays. 
