The "iron blow" at the Linda goldfield

From 1875 to 1877 Mr. Thureau held a position as Lecturer at the Bendigo (Victoria) School of Mines, of "Geology as applied to Mining," Mineralogy; also practical Mining, the Administrative Council of that institution arranged during each winter for a series of public lectures on Popular Science, and at such he elaborated a series of lectures upon the hydrothermal origin of the famous Bendigo Quartz Reefs. He was subsequently elected, upon unsolicited nominations and recommendations, as a Fellow of the Geological Society of London, which honourable position he still holds and treasures.<br>The discovery of silver in the ash or mud, adds, for the first time, this metal to the list of elementary substances observed in the materials ejected from volcanoes, and the addition derived some special interest from the fact of this ash having come from the greatest volcanic (active) vents of that great "argentiferous" zone of the Andes. Small as would be the proportion of silver, it must represent a very large quantity of that metal ejected during the eruption, in view of the vast masses of volcanic ash, etc., distributed over the large area which is indicated by the fall of argentiferous ashes at a distance of 102 miles from the central crater to Bahia de Caraguez.<br>Mr. Thureau states that, if silver, lead, iron, manganese, titanium, chlorium, mercury and other less important metals occur in volcanic ash or mud shown by frequent analyses, as derived, inter alia from the immensely rich argentiferous formations which that gigantic "vent" cotopaxi protrudes; a similar occurrence here on a smaller scale, within a well-known "auriferous zone" is not only feasible, but can be, or is now, demonstrated to be a fact. The only, and to us most valuable difference, is, that the South America ejecta expelled the silver in its ashes, whilst, with our "Iron Blow" the ash or "mud" is still retained within the "dead" vent or closed fissure, and happily for the colony at large, it is comeatable, and it can be extracted by future systematic mining operations, followed by skilful treatment for the rich gold it is reported same contains.