The Ada Tepe deposit is a prime example of a high-level epithermal gold-silver deposit, formed during the Neogene within the Southern Rhodope tectonic zone.

The Ada Tepe deposit is a low-sulphidation adularia-sericite gold-silver epithermal deposit located within Palaeocene sedimentary rocks overlying the north-eastern end of the Kessebir core complex.

The gold precipitates predominantly in the veins. The Ada Tepe deposit shows a multiphase history of formation with several brecciation and vein emplacement events resulting in complex overprinting infill stages and crosscutting relationships between the veins.

Two major styles of mineralisation are apparent at Ada Tepe:
• Initial stage of mineralisation hosted by a massive, shallow-dipping (15° north) siliceous body forming the hangingwall to the detachment and defining the contact between the core complex and overlying sedimentary rocks. This mineralisation is termed the “Wall Zone” by local geologists and displays multiple stages of veining and brecciation.

• Second phase of mineralisation represented by steep dipping veins that exhibit textures indicative of formation within an epithermal environment. These veins have a predominant east-west strike, crosscut the shallow-dipping siliceous Wall Zone mineralisation, and extend upwards into the sedimentary breccia unit above the Wall Zone. This phase of mineralisation has been locally termed the “Upper Zone”.

The ........

The mining methods used at the Ada Tepe pit are conventional excavator and truck methods. Drilling and blasting of ore and waste is conducted over bench heights of 5 m and explosives are delivered to the hole by the drill and blast contractor. Hydraulic excavators are used to achieve good selectivity in conjunction with good blasting practice and mine to a 2.5 m flitch height. Ore and waste are generally loaded to 40-tonne capacity off-highway haul trucks to a ROM stockpile or to the IMWF.

All the production fleet is principally sourced from Caterpillar. In addition to the main equipment units there are graders and water trucks as well as various support and service equipment in use. Mining operations are conducted in two 8.0-hour shifts per day. The mining production rate is about 3 Mtpa total material.

Pit Design
The selected economic pit shell was used to drive the pit design work. The pit design was checked against the Whittle shells to ensure they match reasonably well. The design difference is minimal with less than 3% loss in ore and less than 1% change in total tonnage. This is considered reasonable considering the requirement for ramps and other practical mining considerations.

The ultimate and phase pits were designed following the slope geotechnical criteria and selected pit shell. Four phased pushbacks were used for the LOM plan. All pits were designed on a 5 m mining height. The ultimate pit was designed with 15 m bench he ........

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