The Banket Series in the mine lease areas form prominent, arcuate ridges extending southwards from Tarkwa, westwards through Iduapriem and northwards through Teberebie to Mantraim. The ridge segments are supported by a massive lithological unit known as the Footwall Quartzite, which is a strongly-bedded rock of blue-grey colour exhibiting a sub-parallel haematitic/black sand banding and which locally forms the basal stratigraphic unit to the Banket Reef Zone (BRZ).

The BRZ comprises a sequence of individual beds of quartz pebble conglomerates (Banket beds), breccia conglomerates, metasandstones (also called quartzites and grits). All known gold mineralisation within the Banket Formation is associated with the conglomerates and is found within the matrix that binds the pebbles together. Gold content is presumably a function of the size and amount (packing) of quartz pebbles present within a conglomeratic unit- more pebbles present suggest more gold.

Gold mineralisation is hosted by conglomeratic sedimentary packages referred to as zones or reefs and is considered to be of primary palaeoplacer origin. There are four recognized reefs, namely A, B, C and D and which are equivalent to the Tarkwaian Sub-Basal, Basal (or Main), Middle (or West) and Breccia Reefs respectively. The B and C reefs are oligomictic, and consist of well sorted conglomerates and have been mined underground in some areas for over a century. The A and D reefs have a lower gold tenor and ........

Iduapriem is a multiple open pit operation that currently sources ore from the Block 3W, Ajopa, and Blocks 7 and 8 pits. More recently the Block 5 pit was re-instated in the mining plan.

Mining operations is conducted via mining contractor, AMAX Mining Services. It uses conventional drill and blast, with truck and excavator load and haul.

- subscription is required.

The Iduapriem Mine started operating in June 1992. The original plant, designed to treat about 2.4Mtpa of ore, has undergone several expansions. The most recent expansion work was completed and commissioned in 2009 which incorporated a new 800tph 2-stage crushing plant, a second ball mill at the CIL plant together with a 24 meter diameter thickener, a second Knelson concentrator, and an upgrade of the oxygen plant capacity from 4.0 to 8.0 tonnes per day. The main objective of the expansion project was to increase plant throughput to 4.3Mtpa.

A gravity circuit comprising of 2 XD48 centrifugal (Knelson) concentrators and an In-line Leach Reactor (ILR – Series 1000) recovers free gold (gravity gold) by processing the dense particles from the cyclone underflow slurry. Each circuit has 1 Knelson and part of the cyclone underflow is bled to feed the Knelson.

The concentrator operates in batch mode. Once the preset time has elapsed, the unit goes through a flush cycle ........