HOW GOLD GAME INTO THE QUARTZ REEFS.

Te Aroha News, Volume II, Issue 87, 31 January 1885, Page 7

HOW GOLD GAME INTO THE QUARTZ REEFS.

The following occurs in the Wakatip Mail's report of a lecture at Queenatown by Professor Black, of the Otago University :— The learned lecturer then went on to explain the latest theory accepted as to how gold came into the quartz and quartz reefs. Gold is only soluble in water containing cholorine in tolution, and it then becomes chlorine of gold. If therefore chlo-ine be assumed to have existed in the free state in the water percolating though the mica schist it would dissolve any gold found Here, and the water would carry it it along with tue dissolved silica into the reefs. First it required table salt or chlorine of sodium and saltpetre. The enormous quantity of salt in the sea — which was becoming salter every day — was proof that chloride of sodium existed in abundance in the rocks at some previous period in the earth's history, and had beeu carried down to the sea by streams. {Sulphur was also found in considerable quantities in the rocks that contained gold, and sulphur, when oxidised, formed sulphuric acid, which again acted on the chloride of sodium (table salt) muriatic acid. This acid, acting on the higher oxides of manganese, it was well known formed cl lorine, and chlorine, as above state 1 dissolved gold. The learned lecturer said he believed that he was the first who had propounded the latter portion of this theory, and, if usked in a mien schist country, about the probabilities of the existence "of gold he would deci-luly say if manganese was present there would begold. The existence therefore of oxi-les of m.iHgunesu and of sulphides in quartz reefs in a mica soliist country was a strong indication of gold v\ such reefs. Tii s view was strongly confirmed by his recent ex- i perience of the mines at tile Blue Spur, Tuapeka, and at Naseby, for every claim there contained oxides of manganese. The question was— ls this manganese to ! lie found ovor the rest of tiio country ? Id was of a violet or beautiful pink tint. Nevertheless the country was full of manganese, which made chlorine. He saw it on the top of Ben Lomond that j day, and had little doubt it was to be i fouu Jin the rocks all over the Wakatipu. Practical miners generally asserted that where there was sulphur there would be found gold : but sulphur was simply a link which dragged or precipitated the sold into the reel's — althougu the mica k-cnist k -cnist rock only contained the hundredth part oi a grain of gold.