INTERCOLONIAL.

Otago Witness, Issue 1854, 3 June 1887, Page 12

INTERCOLONIAL.

The Broken Hill Smelting Works during the year in which it has been in existence has produced a total weight of 3891 tons lead, and 1,529,4480z silver— nearly 48 tons. The roughlyestimated value of the year's yield is £385,000. These are big figures, but we (South Australian Chronicle) have no hesitation in predicting that those for the ensuing year will be a long way bigger.

" The Broken Hill Proprietory are now passing through a very rich shoot of carbonate ore, assaying over 400oz silver per ton. The Pootamacca tinfield (South Australia) contains some 15 lodes at least, of which nine are known to be tin-bearing, and would probably average quite 3|ft wide, or equal, if united, to a lode of 30ft wide and six or seven miles long. Assuming from the regularity of the lodes that they go down, as real lodes usually do, there will be work for generations in raising ore, with a money value of enormous amounfe The lodes are of a size that can be worked cheaply, more so than either very small or even very wide lodes. Between drought and floods the miners in the Northern Territory have a lively time of it, and certainly earn their high returns from the quartz reefs. At Croydon during March and April, in consequence of prolonged floods, famine prices

prevailed, flour* realising from 40s to ;50s per 501b ; tea, 5s to 6s, in lots of 51b; tobacco, 7s 6d to 9s, in 51b lots; sugar, Is 0d to 2s 4d perlb, in 101b lots;' rice, 42s per 561b, and so. on. "Fifties" of flour have fetched as high as £5, or 2s per lb, and as much as £6 was paid in one .or more instances. On the 4th April sugar was Is 6d in .the store (where obtainable) ; tea, 7s;' rice, Is 6d ; and preserved potatoes, Is 6d.' The present population of the field is between 2000 and 2500, and is steadily increasing — the state of the weather and the roads notwithstanding. Since the discovery of the first few reefs at Croydon — scarcely 18 months ago— the expansion of the limits of the field has been rapid almost without precedent. Prospecting claims and areas count by hundreds, and there are very few lines of reef on which there are not" " numbers " — more or less. Such lines as the King of Croydon and Highland Mary have from sixto 12 claims, each,, besides the prospecting claims. The veins generally are of good width —some averaging as much as 4ft — and in a great many cases the angle of descent is smallmuch' less than is usually the case in quartz-, mining districts. . Some of the reefs enter the ground almost horizontally, but some of the most productive and best defined have an angle of from 30deg to 45deg ; and in a few cases the descent is almost vertical. For several miles round Croydon the country is thickly intersected with main and cross reefs, the majority of those opened being amply payable, while many are remarkably rich and have every appearance of permanency. Amongst .the principal of those in the vicinity of the town are the Lady Mary, Sir Walter, Highland Mary, Caledonia^ Iguana, Queen of Croydon, King of Croydon, Mountain Maid, Harp of Erin, Mark Twain, &c.; from most of which crushings have taken place at the local machines and have yielded, as much as 13oz2dwt_perton; the average of the whole of the ctushings since the first machine started being about 3foz to the ton. At present there are three crushing machines in the district. The product of the several rich parcels of from six to 40 tons taken to the Etheridge (100 miles distant) to be crushed, added to the gold dollied out on the claims, would raise the average to about' 3|oz to the ton. The Phcenix mine, at Gympie, have just declared a 2s dividend, equal to £2000. This makes the total amount of dividends paid by this company aggregate £262,000. During the past six months the company have raised from their mine 16,200 tonß of atone, the, yield of gold from which aggregated 10,5580fc 15dwt 12gr. The dividends paid during the same period amount to £18,500. The total quantity of stone crushed at the public and private mills at Gympie during the month of April was 9034§ tons, which gave a return of 97480z 18dwt 12gr smelted gold, being an average yield of loz ldwt 13gr per ton ; and the dividends declared during the same period aggregated £16,000. During the first four months of 1887 the quantity of stone raised and crushed throughout the field was 29,577^ tons, yielding 36,2480z 19dwt 6gr gold ; and the dividends paid during the same period amounted to £73,575.

The Sydney Daily Telegraph has the following :—": — " Some novel crushing and amalgamating machinery was to be seen at work yesterday at Messrs Parke and Lacy's works, Pyrmont. The plant consisted first of a crushing machine or stone breaker, which broke up the stone pretty small. From this it fell into a Challenge orefeeder, by which it was automatically supplied in quantities adjusted so as to produce the most efficient work to a Huntington centrifugal roller quartz mill, where it was crushed almost as fine as flour. The ore-feeder seems to be a very valuable invention. The theory is thus stated by the • exhibitors :— ' Take an ordinary hand mortar and pestle and 'attempt to pulverise a quantity of quartz ; drop in but a small quantity, just sufficient to cover, in a thin layer, the bottom of- the mortar, and it will rapidly pulverise under the blows of the pestle ; drop in a larger quantity and the blows of the pestle will be ineffective and the time and labour lost in the effort to reduce it to powder. In this lies all the open secret of the theory; therefore, so adjust the rod leading to the lever bar of the ore-feeder that the Jbtroke of the tappet shall cause it to 'feed low,' and then the desideratum "of the 'largest quantity of ore milled in the shortest period of time will be attained.' , The Challenge is so adjusted as to secure this desideratum, and appeared to do its work perfectly — a remark which ;*lso applies tn the Huntington cent) i-.gali -.gal ro'ler n- •, :•■ machine little known, in Nt.? South W;-.leb .-.ad which we described a few days ago. From the crusher the finely-pulverised ore descends over silvered plates, and isfinally delivered to two Frue vanners. These were also hhmvu at work, but a-, the stone contained little or no pyrites or concentrates, the peculiar merits of the " vanners " in saving this class of ore was not displayed. Free gold was- visible in the stone put through, but nearly the whole was saved in the pulveriser, which is also an amalgamator. At a future date, we understand, the Frue vanners will -be shown in operation on tin ore, for the separation of which they seem admirably adapted. After the first feeding of the ore-breaker all the other machines are so placed that the ore feeds itself by gravitation, an admirable labour-saving contrivance."