POSSIBILITIES FOR ECONOMIC VALORIZATION OF SMALL COAL DEPOSITS IN THE REPUBLIC OF MACEDONIA

5th International Scientific Conference - SGEM2005, www.sgem.org, SGEM2005 Conference Proceedings/ ISBN: 954-918181-2, June 13-17, 2005, 169- 176pp

ABSTRACT

In this study, diagnostic leaching and ultrafine grinding as pretreatment step ahead of
two-stage cyanidation of Kaletaş ore were studied to shed light on the refractory
characteristics of ore. The overall gold extraction of 93% was achieved in two-stage
cyanidation of ultrafinely ground ore suggesting the presence of readily recoverable gold
(74%) and slowly reacting gold (19%) in the ore. Diagnostic leaching approach provided
information into the cause of the refractoriness of the ore. The findings of diagnostic leaching
tests suggested that the refractoriness could be due to the dissemination and encapsulation of
the very fine gold particles largely within the carbonates, oxides and sulfides and, to a small
extent, within silicates present in the ore matrix .