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extend for 3 or 4 miles. The first rocks noted appear to be tuffs made 
up largely of small fragments of slate; higlier up the creek these rocks 
are succeeded by tuffs, porphyries, and felsites. On the east bank 
of the stream, however, about three-quarters of a mile above the bridge, 
there is an inlier of decomposed pale-yellow rocks, either decomposed 
slate or fine tuff of the porphyry-felsite series, in which a slaty struc¬ 
ture has been developed. They show some obscure markings, preserved 
as a thin silvery greenish streak, which may have been caused by 
vegetable remains. 
Iron Ore, Limestone, Barytes, and Other Minerals. 
Micaceous iron ore occurs very freely in the porphyry-felsite, and 
very sparingly in the Ordovician series. I did not visit all the out¬ 
crops in the district, but along the tourists’ track to Buchan there are 
some of high-grade iron ore a chain or more in width. Throughout 
the porphyry-felsite series barytes and red jasper occur irregularly, the 
latter sometimes plentifully. Manganic iron ores occur at the Iron 
Mask mine, and at other places along the Tara Bange, south-east of 
Buchan; fine-grained rocks have been so saturated with iron-bearing 
solutions that they now constitute a fair grade iron ore; from a surface 
inspection, it is not possible to say whether these fine-grained rocks are 
altered members of the felsite or Upper Ordovician series. 
About 3 miles east of the Buchan accommodation house, on the 
Bruthen-road, at Oanni Creek, I noticed micaceous iron ore in rocks 
belonging to the porphyry-felsite series. An outcrop of Middle 
Devonian limestone, the nearest to the Bruthen-Orbost railway, occurs 
at the accommodation house. The white mica and quartz veins carry¬ 
ing pyrites, so noticeable in the Ordovician rocks, seem to be absent 
from the porphyry-felsite series. 
I was asked to inspect a silver lode below the Ironstone Creek 
bridge. A quartz reef, about 3 ft. thick, occurs in hard slate and sand¬ 
stone ; it is in centre country, pitches underfoot to the north, and is 
heavily mineralized for two-thirds of its width with iron pyrites, and 
to a lesser extent with arsenical pyrites. A portion of the reef decom¬ 
posed to a gossany quartz is said to contain some very fine gold. 
In the bed of the stream a hole has been sunk for a few feet, but 
the exposure is very limited. A ton of quartz is said to have been 
treated as a bulk assay, and yielded 80 oz. of silver and 13 dwt. 
of gold per ton; but samples collected by me, and assayed at the Geolo¬ 
gical Survey laboratory, gave very poor results, and indicated that the 
reef was not payable. 
Summary. 
In the Uowa ISTowa district there are, omitting the Tertiaries, three 
predominant series—the Upper Ordovician, the felsite-porphyry series, 
and the Middle Devonian marine limestones. 
The Upper Ordovician sandstone near Uowa Uowa contains a con¬ 
siderable quantity of mica and irregular quartz veins, intersected with 
veins of iron pyrites. Uear Boggy Creek bridge this series is folded, 
and pitches steeply, dips up to 70° being observable. 
The slates and mudstones along the Tara Range are fossiliferous, 
yielding in places Upper Ordovician graptolites, and in other places 
passing into cherts not unlike those at Longwood, Heathcote, and else¬ 
where in Victoria. 
