The Akoluk ore deposit is located in southwest of Ordu city (Turkey) and in the western part of the Eastern Pontides, which consists mainly of volcanic-sedimentary rock units. Gold and silver contents of the ore are 20 and 220 g/ton, respectively. The chemical and mineralogical characterisation of the ore showed the presence of quartz/clay (52.2 per cent SiO_2) and barite (17.1 per cent Ba) as the predominant phases, and sulfides, to a less extent. Some gold and silver were found to be associated with framboidal pyrite and Sb sulfides. The extraction of gold and silver by cyanidation was considerably low, ie ≤47 per cent Au and ≤19 per cent Ag and did not improve through fine grinding before cyanidation. In this study, the application of roasting on refractory Akoluk ore as a pretreatment step prior to cyanidation was demonstrated. The results of subsequent cyanidation step after roasting tests indicated that the recovery of silver could be improved from <19 per cent to 30 per cent Ag at the temperatures of 400 - 500°C while gold extraction was adversely affected at >200°C. Water leaching of the calcines produced at 500°C was found to improve the extraction of gold and silver, to some extent.
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