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7. GOLD IN THE WAIHAHA AND MANGATU, TAUPO. (By L. I. Grange.) In December, 1927, the writer visited the Mangatu prospecting party's camp in Mangatu Stream, about a mile and a half below Weraroa Trig. Station. The Mangatu is a large branch of the Waihaha, a considerable stream flowing into Western Bay, Lake Taupo, from the Hauhungaroa Mountains. The party, under the leadership of Messrs. Tennent and Raymond, had for several months been actively prospecting the gravels of the Waihaha and Mangatu, and the quartz Veins of the upper valley of the Mangatu. Since the prospectors returned to Waihaha the day after the writer arrived at their camp, his examination of the country was necessarily hasty. Waihaha, a small Native village in Western Bay, is reached by launch from Taupo Township. From it a track, in places ill-defined and fairly rough, leads to the head of the Mangatu, a distance of about fifteen miles. The geology of the area is fairly simple. Prom the western side of Lake Taupo, north of Karangahape Cliffs, an upland surface of low relief extends westward to the foot of the Hauhungaroa Range. Close to the lake-shore it is 1,620 ft. above sea-level, two miles inland about 1,850 ft., and eight miles from the lake about 2,000 ft. On the coast the upland surface ends abruptly in cliffs which rise sheer from the edge of the lake (1,211 ft.). The main streams flowing down the slope of the upland surface are deeply entrenched, the valley-bottoms in places being fringed by precipitous cliffs. Farther inland the country rises to Moutere (3,248 ft.), Weraroa (3,580 ft.), Pareora (3,793 ft.), and other peaks of the Hauhungaroa Range. The upland surface is composed of hard, well-jointed, rhyolite tuff similar to that occurring on the Kaingaroa Plains, with which, before the collapse and subsidence of the Lake Taupo basin, it was probably continuous. Argillite and greywacke of early Mesozoic or late Palaeozoic age, outcropping in the valley-bottoms of some of the tributaries of the Mangatu for more than three miles of its course down the southern slope of Weraroa Mountain, show that the thick rhyolite tuffs occurring on the mountain are only a surface covering. The irregular distribution of the tuffs in the Mangatu Valley indicates that prior to the eruptions deep valleys had been carved in the old rocks. The strike of the old sediments, in the few places it was taken, was north and south, and the dip eastward at 60°. These rocks also outcrop in the head of the Waihaha, Stream, since the gravel in it is almost entirely of argillite and greywacke. The gold-bearing gravels near the mouth of the Mangatu and in the Waihaha were first prospected. Later the alluvial gold was traced up the Mangatu, in the valley of which the quartz veins were searched for. The prospectors state that they obtained as many as ten small " colours," occasionally reaching the size of a pin's head, from dishes panned in the Mangatu, and that concentrates of a yard of gravel from this locality was found on essay to contain a value of Is. 6d. in gold. The writer panned a quarter of a dish of concentrates, consisting almost wholly of magnetite sand, and found eight angular " colours " ranging in size from s to in. Thick gold-bearing gravels extend for about half a mile up-stream along the Mangatu, and a stretch of gravel about a mile long in the Waihaha is probably gold-bearing. Altogether very little data have yet been obtained. The wash in the Mangatu has not been bottomed, the depth of gravel and its average gold content are not known, and much more prospecting would, of course, be required to get an idea of the return that could be expected. The alluvial gold probably comes from quartz veins in the old rocks forming the range. The writer was shown two crush-zones carrying quartz, calcite, and pyrite. One, called December " Reef," 2,350 ft. above sea-level, about one mile and a quarter south of Weraroa Trig. Station, strikes 15° east of north and dips steeply westward. The crush-band is about 4 ft. wide, and contains much pug. The other, called Hades, in a tributary from the west about one mile and a half below the Trig. Station, strikes 30° east of north and dips eastward at 70°. The greywacke here is not so much shattered. Samples from both crush-zones assayed by the Dominion Analyst were found to contain no gold or silver. Country in the North Island formed of the same set of ancient rocks has been prospected from time to time in the last fifty years, and although small colours of gold occur in many streams, no alluvial or vein deposit worth working has been found. Rich quartz may be located, but in such country the vein will probably be discontinuous. One cannot say that payable ground or quartz veins will not be found, but the chances are small. J. Henderson, Director, Geological Survey. REPORT OF THE DIRECTOR OF THE METEOROLOGICAL BRANCH. Observing-st ations . Two different classes of meteorological station have been evolved in New Zealand, each serving a distinct purpose. The first class was designed to provide the information necessary for the daily report and forecast. The first condition controlling the choice of these stations was that they should be readily accessible by telegraph, so that reports could be sent to Wellington with the minimum delay. They have, in general, therefore, been established in connection with post-offices, lighthouses, or Harbour Board offices. The instrumental observations are generally confined to those of pressure and temperature. A high standard of accuracy has not, in most cases, been aimed at. The barometer corrections, particularly that for height above sea-level, have been approximate only. The thermometers

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