QUICKSILVER.

Otago Daily Times, Issue 181, 14 June 1862, Page 5

QUICKSILVER.

In the face of the- reputed discovery of quickBilver at Tokomairiro, any information concerning it is likely to prove interesting, especially as it is a metal which, as before frequently stuted, might be looked for in New Zealand- On the value of quicksilver in the arts, and for mining, manufacturing, and scientific purposes, it is scarcely necessary to dwell. Suffice it, from the earliest ages it has been in demand, and.the larger the production, the larger apparently the use for it. Its high price prevents its being used so generally in the production of gold as it might be. That it can be useu with advantage may be gathered from thefact that Humboldt, when in Southern America, calculated that the consumption of quicksilver in the treatment of the gold and silver ores in the mines of New Spain, amounted annually to 1,600,0001b5. Dumas estimates the following annual yields from the principal mines : —Almaden, in Spain, from 2,700,000 to 8,45G,0001b5.; Idria, 648,000 to l,O80,OO01bs.; Hungary and Transylvania, 75,600 to 97,20D1b5. ; Deux Points, 43,000 to 54,0001b5. ; Palatinatf, 19,440 to 21,6001b5.; Huancavelica, 324,0001b5. Besides this, Ihe more recently discovered mines of New Almaden, in California, are calculated to yield annually 1,000,0001b5. Quicksilver is a heavy-metal, having a specific gravity or density of thirteen, decimal six. By way of contrast, we may mention that the specific gravity of gold is nineteen, decimal three, whilst that of quartz is only two, decimal six." So that Quicksilver is about five times as heavy as quartz, and one third less heavy than gold. It occurs in various forms in nature, but almost invariably it ■will be found in a native state in the crevices of the rocks from which mercurial ores are obtained. "It appears," says Mr. Robert Hunt, " thitt the mercurial de- " posits are confined within very narrow geo- " logical limits, between the calcareous beds of " zechstein and the red-sandstone. They oc- " cur at times in carbonaceous nodules, de- " rived from the decomposition of mosses of " various kinds, and the whole mercurial " deposit is occasionally covered with beds of " lignite." Quicksilver is found in nature, as we have said, in various ibrms. The argental mercury — a combination of silver and quicksilver—occurs in many of the large mercury mines, but in sparing quantities. It is of a silver white color, and is more or less soft,' according to the quantity of mercury it contains. Chloride of mercury, or horn mercury, occurs in small crystals, of a pearl grey or greenish grey, associated with othefMacrcu rial ores. It also is very rare. By far Jme7 most abundant source of quicksilver is the red cinnabar or sulphide of mercury. Of this mineral the principal quicksilver mines are composed ; its form varies sometimes, with local circumstances. Its general character may be described as red of various shades, of a specific gravity, varying from 6.9 to 12.2, according to its purity. In other words, from two and a-half to four and a-half times as heavy as quartz. In Idria the cinnabar is of a bituminous character. It is of a dark liver-red hue, and of a slaty texture, with straight or twisted plates. The impressions of fishes are sometimes curiously spotted on it. Sometimes the cinnabar js strongly mixed with sandstone. In California the cinnabar is of a bright vermillion color. Cinnabar is easily detected by its great weight, aud by the facility with which, on

the application of the blowpipe, it will give off mercurial flames. The powder of the ore also, on being rubbed, over copper, will whiten it. Quicksilver is sparingly distributed as far as the number of mines goes, but thesejmines are, some of there, enormously prolific. Pliny records that quicksilver was procured from Alrnaden, in Spain, " 700 years before the '• Christian era, and that, in his time, Rome " was annually receiving 700,0001b5. from the "same mines."- Since 1827, the mine has yielded 2-2,ooocwt. of quicksilver every year, with a corps of 700 tinners and 200 smtlters. Although Almaden has been worked for many centuries, the ore is so prolific that it is not yet worked down to a 1000 feet. The lode is from 14 to 16 yards thick. The Idrian mines, it is said, coufd be made to yield 600 tons of quicksilver yearly, but, to keep up the price, the Austrian Government restricts the quantity to 150 tons. Perhaps we cannot conclude this short notice more appropriately than by quoting from Dr. Tobin's account of the mercurial mines in California—the latest found large deposit of the metal: —

Tliat part of California where I have been residing, and that which 1 have' just visited, consists of throe long ranges of trap mountains, with two wide valleys dividing them —the valley of the Sau Joaquiu and the valley of Santa Clara. Near this last place are the quicksilver mines of Now Almaden, whera ,1 have been working. The matrix of the cinnabar ore is the same trap of which the mountain ranges are composed, and as yet only one great deposit of this ore has been found, though trace 3of quicksilver ores have been discovered in other places. The ores are composed solely of sulphurot of mercury (averaging 3o per cent.), rei oxide of iron and silica ; and. had the mine been properly worked from the commencement, almost any quantity of ore might be extracted: it now, however, more resembles a gigantic rabbit warren than a mine. The owners have lately sent out a German miner, an experienced and practical man, who, if he stays here, will eventually put the mine into some kind of order. Its greatest depth is about 150 feet, aiid the weakly extraction of ores varies from 100 to 150 tons.