QUARRY FACE BLASTED

Taranaki Daily News, 11 August 1930, Page 16

QUARRY FACE BLASTED

MANY TONS OF EXPLOSIVES. I — The largest blast that has ever been exploded in New Zealand was fired at Wilsons Portland Cement Company’s quarry at Portland, near Whangarei, on Wednesday.For the past eight months preparations had been made and the whole quarry face was lined with veins containing gelignite. Before the explosion the quarry face overhung a height of 260 ft. of sheer lime-stone at the highest point. At a point 40ft. back from the edge 25 holes had been bored, the deepest 245 ft., and tho shallowest 125 ft., containing 25 tons of high explosive, • four tons more than the previous record blast made by the company. The blast was the most successful ever held and material sufficient to feed the works for two years now lies at the foot of the quarry. The rock has been broken up to such an extent that very little pick and rhovel work will be necessary to load it Into the trucks. For several hours after the explosion small quantities of stone became loosened and plunged down the quarry’s new face and into the piled up debris at the foot.