THE FLOTATION OF "YELLOW ORE" FROM HANAOKA MINE

Microscopic Study of Mill Products and Batch Flotation Tests

Abstract

The so-called "yellow ore", which is the most important among three kinds of run-of-mine ores at the Hanaoka concentrator, yields the copper concentrates of poor grade, because of the insufficient depression of pyrite. It is probably due to the difficulty of liberation of pyrite from copper minerals, as well as the semi-oxidation and contamination of mineral surfaces underground.
In order to solve this complex problem, the authors have made the experimental research at the Mineral Dressing Laboratory, University of Tokyo. The microscopic study of several flotation products from the Hanaoka concentrator was conducted, being followed by the batch flotation tests. It was shown by the microscopic analysis that the liberation of copper minerals from zincblende was rather easier than that of copper minerals from pyrite on account of the inherent mineral textures of the ore. The role of sodium cyanide and also the effect of finer grinding were established to some extent by two series of batch flotation tests.