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The Quartz Ranges auriferous deposits are for the most part in place as originally deposited, and occur at levels varying from 950 ft. to 1,550 ft. above the level of the sea. They extend southwest from the brink of the great chasm of Salisbury Cfeek to the fall into the lower valley of Clark s River. The gravels are all locally derived, and towards the south-west contain large boulders of quartz and quartzite, or highly siliceous schist. The whole has the appearance of having been deposited in a valley depression declining from south-west to north-east, and bounded as already described by Pine Ride on the one hand and the broken ridge of the Quartz Ranges on the northwest side. ;, ... Within the northern and middle parts the chief bodies of wash he on the south-east side ot the valley. South-west of Maori Creek the filled-in depression has been cut across by the lesser streams of modern date that find their way from Pine Ridge to the Aorere. Consequently, on the ridges between the beds of these streams the auriferous drifts form deep ground, extending from spur to spur along the line, but not showing in the beds of the intervening creeks which have cut through the gravels to the bed-rock. . The average breadth over which the auriferous gravels are exposed is between 7 and 8 chains, and the thickness of the deposit varies from 4ft. or sft. to 50ft. The gravels are generally auriferous, but towards the south-west, and where the wash is coarse, the gold is chiefly in the last 2ft. or near the bottom of the gravels. Towards the north-east the wash is finer, and the gold, apparently, more evenly distributed throughout the wash or lower part of the gravels. Outside the particular depression along which these auriferous drifts have been deposited there is little wash in the immediate neighbourhood, but down the slope there are several bodies of gravel that have already been alluded to. No payable gold-wash has been found in these outside deposits. The gravel-deposit hitherto worked for gold therefore extends from Salisbury Creek south-west a distance of about, or fully, two miles. The area is for the niost part taken up as special extended claims for mining by means of hydraulic sluicing. In the south-west part the area held by West, Adams, Fell, and Co. is to a large extent untouched, and towards the south-west extremity of their holding the ground appears to be deep and involved along the south-east side, after the manner of the same deposits on the south-east side of Golden Gully. Along this side the quartz-drifts are cemented or indurated into a hard rock resembling brecciated quartz. These quartz-cements protrude above the general surface like outcrops of reefs, for which they have been mistaken. More to the north-west the gravels are not cemented, and one or two holes have been sunk in them to a considerable depth. I could not learn with what results. On the north-west side the ground shelves to shallow, and the quartz-drifts again appear, but resting at low angles on the schist-rock. Towards the north-east in this part the wash is coarse, and large boulders are plentiful in it. The wash, also, is to some extent cemented, or, at least, solidly compacted, but not so much but that it may be easily worked under a good head of water. Though requiring considerable pressure to pull it down, the gravel treats well after it has fallen. The gold is shotty, or coarse, occasional pieces weighing up to half an ounce being met with. . _ . The middle area, held by Ziman and Company, does not show such deep faces of dntt, and the wash lies mainly on the slopes of the south-east side of the valley depression along which the gravels extend. In the lower part Graham's Spur shows a considerable area over which there is a good depth of gravel and wash. Over this section gold-workings have been carried on at many places. Large stones occur in the wash here, but they are not so abundant as farther to the south-west. The wash is rather hard, and generally harder than in the workings more to the south-west. This area is not quite so favourably situated for getting rid of tailings, though at the same time the conveniences for the disposal of these are sufficient. The gold here proves to be as coarse as further to the south-west. The north-east end of the auriferous belt is held as a special area by West, Adams, -fell, and Co , and in respect of its position, the character of the material, and the favourable situation for 'disposal of tailings this area has distinct advantages. The breadth of the deposit is at first towards the south-west boundary, somewhat restricted, but it gradually widens to the north till where it terminates in Salisbury Creek the width is as much as on any part of the line. The middle and northern part of this area is decidedly, as a field for sluicing, the most promising part of the Quartz Ranges. The ground gives evidence of being generally gold-bearing, being riddled with holes and in part driven out from these or from the brink of the deep ravine of Salisbury Creek. The wash is finer and less tightly compacted than more to the south-west, and consists more of quartz than in the other parts of the Quartz Ranges. The gold also appears to be distributed throughout the whole depth of the wash, and the get-away for the disposal of tailings is into Salisbury Creek, which runs in a ravine 500 ft. below the level of any workings likely to be opened out. To reach this ground, if taken from Clark's River, the water would have to be brought along the top of the terrace and ridge to the south-east of the run of gravels, and to obtain sufficient pressure perhaps a greater length of pipe-line would be required than to most parts of the other holdings. The water intended to work the auriferous deposits of the Quartz Ranges is proposed to be brought from Clark's River or from Boulder Lake ; probably from the first-mentioned source, in which it is said there is a minimum supply of forty Government heads. The race has not yet been surveyed, and it even appeared doubtful, when making inquiries on the subject, if the whole line of it has been closely explored. And not having been over the ground, nor seen Clark's River at the point at which the water will have to be lifted, I can express no opinion as to the volume and permanence of the water-supply, nor the height overlooking the Quartz Ranges to which it can be brought. The principal areas over which auriferous deposits of this age are found have now been described; and, as there has been included under this head deposits which by other geologists have been regarded as belonging to a different period, something more will have to be said in support of