i

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There is a good show of this ore at Hikurangi, but the expense of carting it prohibits the deposit being worked. It is stated that mining will be again resumed for this mineral in Kawau, from which 320 tons were shipped in 1890. The Helena Bay deposit is said to be very poor, but the deposits at Mangapai are large and payable for working.

DISCOVERY OF GRANITE ROCKS IN THE KING-COUNTRY. An important discovery has recently been made by Mr. James Park, F.G.S., Director and Instructor of the Thames School of Mines, who visited the King-country for the purpose of examining a locality where granite rocks were thought to exist. Rumours have at various times reached the department that tin was found in this part of the North Island, and on several occasions Captain Jackson Barry stated to me that he had found it; but as there was no record of granite rocks being found in the North Island, the statement as to tin-ore being discovered seemed rather improbable. However, it is but fair to state that Mr. Park found granite rock in situ on the left bank of the Mangaone Stream, about twenty chains above its junction with the Turetea River, which is a tributary of the Waipa River, and junctions with it about four miles south of Alexandra. This was near the locality where Captain Jackson Barry stated he had found tin-ore. The discovery is therefore the more important, as it shows the probability of tin being found. Further explorations may show that granite and granitoid rocks extend over a large area in this portion of the country, which has hitherto been but little explored. The following is Mr. Bark's report on the discovery : —■ "Thames, 25th April, 1892. " I have the honour to report that, in accordance with your instructions of the 15th March, I left the Thames on the 17th instant, and proceeded by steamer to Auckland. On the 18th I reached Otorohanga, and next day, accompanied by Mr. George King, of Otorohanga, and Mr. George Ormsby, of Alexandra, I visited and examined the locality where the granite rocks occur. On the 21st I returned to the Thames. " The circumstances which led to the discovery of granite and granitoid rocks in this Island are briefly as follows : Mr. Charles King, some six months ago, while mustering his sheep in the Mangaone Valley accidentally found what was to him a new and peculiar rock, and one which he thought from its great weight and colour was likely to contain either gold or silver. Aided by Mr. Ormsby and Mr. Griffiths, of Alexandra, the latter an old alluvial miner, the locality was thoroughly prospected for gold, and one or two ' colours ' are thought to have been found in the wash-dirt in the bed of the Mangaone Stream, and some fragments of granite, crushed and washed by Mr. Griffiths, were also believed to have yielded a speck or two of the precious metal. " After this a number of pieces of granite and associated rocks were handed to Mr. G. T. Wilkinson, J. 8., Government Native Agent at Otorohanga, who forwarded them to Mr. T. L. Murray, the manager of the" Bank of New Zealand at the Thames, for assay. The result of these assays showed that gold and silver were not present in these rocks. " Some time towards the end of February Mr. Max yon Bernewitz, the assayer to the bank, showed me a number of these rocks, and I at once identified examples of true granite and granitic gneiss among them. Mr. Murray informed me that Mr. Wilkinson stated in his letter accompanying them that plenty more of the same kind could be got if necessary. I then placed myself in communication with Mr. Wilkinson, to whom I am greatly indebted for many specimens and much valuable assistance in making arrangements for facilitating and furthering the object of my visit to the Kingcountry. " The exact place where the granite is found is situated on the left bank of the Mangaone Stream, about a quarter of a mile above its junction with the Turitea Biver, which rises among the wooded Tapuaea hills, lying two miles east of the Hauturu Bange, and falls into the Waipa Biver four miles south of Alexandra. " From Otorohanga southward to the Upper Mokau Valley and westward to the sources of the Waitomo and Moakurarua Streams the country is occupied by long low undulating or flat-topped ridges and spurs, covered with deep rich soil, supporting a dense growth of fern and tutu. There is evidence in many places to show that this area was at one time covered with a great forest, the remains of which may be traced in the numerous small isolated clumps of bush which still exist on sheltered slopes and in deep valleys. These open fertile ridges are principally composed of soft green and yellowish-coloured sandstones, often interstratified with crumbling blue marly clays. Both the sandstones and the clays contain an abundance of marine shells and corals, and where there is an excess of calcareous matter, which is usually in their lower horizons, they pass into a hard semicrystalline limestone, in many places of great purity and much value for building, agricultural, and mortar purposes. The rocks are of Cretaceo-tertiary age, and form an important and well-marked series of the coal measures of New Zealand. In this district,, as at Baglan, Kawhia, Mokau, and Upper Wanganui, they are distinguished by the presence of valuable seams of superior brown coal, occurring generally at the base of the formation at or close to the point where it rests on the eroded floor or basement-rock of the country. It is, however, a noticeable circumstance that where the hard semi-crystalline limestone rests on or approaches the old rocky floor the coal is usually absent, or represented only by thin streaks of carbonaceous matter. This is also a characteristic feature of the coal measures around Whangarei and Kawakawa, and it would tend to show that the limestone and coal were, at least in part, the result of contemporaneous developments or growths, the former on a sea-bottom, the latter on low-lying swampy areas contiguous to the sea. " Where coal exists in the Waipa and Mokau districts, the limestone does not attain its greatest development, but passes downwards into soft yellow or brown-coloured sandstones, often coarse-grained, gritty, or pebbly, with fireclay and coal seams at their base. " From the sources of the Waipa the coal measures stretch almost uninterruptedly to Kawhia Harbour and the West Coast, but on the south slopes of Mount Firongia and the Hauturu Bange