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The Glenorchy lode is on the flanks of Mount Judah, east of the gorge of the Buckler Burn, 600 ft. above the streaiu and about a mile and a half east of the village. It is worked by means of eight adits, the lowest of which is about 2,000 ft. above sea-level and the highest 2,250 ft. It strikes east-south-east northward at about 12°. The dip is so flat that the strong smooth walls, polished by movement and up to 8 ft. apart, might almost be spoken of as roof and 'floor. The filling consists pnncipally of crushed country and quartz ; calcite, scheelite, pyrite and arsenopyrite occur in smaller amount. There is usually a little gold, and at a few points rich auriferous quartz has been found. A battery concentrate from ore mined from adits 10 and 1a contained 42-95 per cent, of W0 3 , 8-15 per cent, of pyrite, 16-24 per cent, of arsenopyrite, as well as 19-5 dwt. of gold per ton. Tung'stite, the yellow powdery oxide of tungsten, has been seen near the outcrops, but is rare. The quartz is more or less continuous throughout; the face of a drive practically always shows some quartz. It occurs in flat lenses of very different sizes, usually within the lode filling, but'in places directly against one or both walls. The lenses may overlap, being separated by bands of crushed country. This latter forms a substantial part of the fissure-filling and consists of schist fragments in a matrix of comminuted rock. It is traversed by veinlets of quartz as well as by many slicken-sided partings blackened with graphite. Ihe whole is hard and compact, though it tends to disintegrate on the dump. There are minor irregularities in the lode as well as breaks heads and small faults.

' The quartz is generally laminated, owing to the presence of thin dark layers of " mullock," and this may be interpreted as evidence of the replacement of crushed country by lode minerals. The scheelite occurs m small stringers, bunches, and patches in the crushed rock and the quartz, as well as being disseminated more or less irregularly in quartz lenses of considerable size—i.e., 1 ft. thick and 30 ft. to 40 ft. long. It is usually more plentiful near heads, breaks and faults, and in downward " rolls " of the lode. Calcite occurs at many points with the scheelite and is considered a favourable indication for the mineral. Near the outcrop the calcite has been dissolved, and perhaps on this account much of the scheelite near the surface, and indeed the ore as a whole, is more friable and porous. The sulphides occur chiefly with the broken schist, and where found in quartz are usually near the dark graphitic bands. The ore is distributed along two more or less definite shoots which are separated by a part of the lode which is barren, or at least contains material not worth extracting. Though considerable movement. has taken place along the lode fissure, the country, apart from the crushed rock within the fracture itself, is not greatly disturbed and the schistosity planes near the lode maintain tjheir strike of about 20° west of true north and their westward dip of about 40°. In plan the lode fissure, which strikes about 17 u south of east and dips northward at, say, 12°, truncates the schist planes on lines which strike about

SKETCH MAP OF LOWER BUCKLER BURN GLENORCHY

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