The Kisladag deposit is hosted by a suite of subvolcanic monzonite porphyry intrusions that are subdivided into Intrusions #1, #2, #2A, and #3. Intrusion #1 is the oldest, and generally best mineralized phase. It forms the core of the system, and is cut by the younger porphyritic intrusions. It is an E-W oriented elongate elliptical body in map view (~1,300 m x ~500 m), and in the subsurface has a sill like form intruding along the contact of the basement and volcanic package (Figure 8-1). At depth the main body extends beyond the current limit of drilling (~1,000 m). Contacts between Intrusion #1 and the surrounding volcanic rocks are generally obscured by alteration. Contacts with younger intrusions, particularly Intrusion #3, are better preserved. Intrusion #1 has a K feldspardominant groundmass with plagioclase phenocrysts (up to 30% of the rock by volume), occurring as tabular crystals ranging in size from 0.1 – 5 mm. Biotite is the second most abundant phenocryst phase (up to 10% of the rock) whereas blocky megacrystic K-feldspar phenocrysts, up to 1 cm, are a characteristic of this unit, but are low in abundance compared to plagioclase and biotite phenocrysts (< 2%). Quartz phenocrysts are rare, and are generally rounded or embayed where present. Intrusion #1 lacks amphibole or pyroxene phenocrysts and primary magnetite.

Intrusion #2 occurs as a WNW-oriented elongate body at depth that splits into two apophyses that form semi-circular stocks (both approximately 150-200 m in diameter) at shallower levels where they cut Intrusion #1. Both apophyses are in contact with and cut by Intrusion #3. The rock is a fine- to medium grained porphyry with abundant (20-30%) plagioclase phenocrysts up to 2 mm in length in a dominantly K-feldspar groundmass. Rare primary biotite and amphibole phenocrysts occur but the unit lacks quartz phenocrysts. Very fine-grained (< 0.2 mm) primary magnetite in the groundmass may be primary.

Intrusion #2A occurs in the southeast corner of the pit and is characterized by a very intense clay (kaolinite-smectite-pyrite) alteration throughout that forms a distinct textural and rheological argillic altered sub-domain termed the friable domain. Intrusion #2A forms a circular stock (250-300 m across) that tapers at depth. It intrudes the margin of Intrusion #1, but contact relationships with Intrusion #3 are not observed. It is a fine- to medium grained porphyritic rock, but the intense pervasive clay alteration obscures the primary mineral assemblage.

Intrusion #3 is the youngest large intrusive body. It forms a semi-circular stock near the center of Intrusion #1, west of the central Intrusion #2 stock and at depth to the west extends into a WNWelongated, subvertical dike like body. Intrusion #3 is a fine-grained porphyritic unit with 20-30% plagioclase phenocrysts up to 4 mm in length, and lesser quartz and biotite phenocrysts (both < 5%). Amphibole phenocrysts (5-10%) are more abundant than in the other intrusions but are commonly altered to chlorite. This intrusion is magnetic due to the presence of very fine-grained disseminated primary magnetite in the groundmass.

Porphyry-style sheeted to stockwork quartz veins occur with the potassic and white mica tourmaline alteration zones. Veinlets range in width from 0.1 mm to 1 cm, with most being 1-3 mm. Gold occurs as non-refractory, very fine free gold grains (typically less than 10 microns in diameter) that are associated with pyrite, and less commonly other sulfide phases (chalcopyrite, and sphalerite), as well as free grains attached to quartz, K-feldspar and albite. Both native gold and electrum (with up to 18 % Ag) have been identified. Other opaque minerals include pyrite, molybdenite, and sphalerite, with minor occurrences of tennantite, tetrahedrite, bournonite, chalcopyrite and gold- and bismuthtelluride. The average copper grade of the deposit is low (~ 200 ppm) but increases to typically between 300 and 500 ppm within potassic alteration (Baker et al., 2016).

The mine is an open pit delivering 13 Mtpa to the crushing circuit with a life of mine strip
ratio of approximately 1.29:1. Mining methods are by conventional open pit techniques with unit operations consisting of drilling, blasting, loading, and hauling by truck.

Ore and waste are mined in 10 m benches with truck hauling of ore to the primary crusher on the north east of the pit and waste to the south rock dump centered approximately 1 km south of the western edge of the pit.

The pit will be developed in four phases. The first two have been completed and mining of phase 3 is ongoing. The final pit will be approximately 1,360 m (east-west) x 1250 m (north-south) x 505 m deep.

The Kisladag ore is processed in a standard heap leach facility containing a three stage crushing plant, an overland conveyor to the heap leach pad, mobile conveyors and a stacker for placing the ore and a carbon adsorption facility (ADR plant) for recovering the gold. The carbon is treated on site in a refinery and the final product is a gold doré bar.

The primary crusher is a 1,270 mm by 1,651 mm gyratory crusher capable of processing the ultimate design rate of 1,751 t/h. Run of mine ore is hauled from the open pit and direct dumped into the primary crusher. Initially, contract miners delivered the ore in 37 tonne trucks and the layout provides for two trucks dumping simultaneously. The dump pocket has a capacity of 300 tonnes and is adequate for the larger owner operated mine trucks in later years. Owner operated mining training and transition with 150 tonne trucks started in May 2008. In October 2008, the mine started to use its own equipment. The crushed ore is conveyed to a 20,000 tonne coarse ore stockpile. This is used as surge capacity to feed the fine ore circuit. Material is then conveyed from the base of this to a 300 tonne coarse ore bin and then on to the secondary crusher.

The final crushed product was prepared in a circuit consisting of one scalping screen, one MP1000 standard secondary cone crusher, three MP800 short head tertiary cone crushers, and four fine ore screens. The capacity of the circuit ranges from 1,300 t/h to 1,400 t/h when delivering a product containing 80% passing 6.3 mm.

Final product from the crushing and screening circuit is transported to the heap leach pad by two stage overland conveyors and a series of portable conveyors. A radial stacker distributes the ore onto the pad. Depending on the location and geometry of the pads, advance stacking is applied as well. Stacking is carried out in 10 m lifts to a projected design height of 60 m.

When the overland conveying is not available, to keep the crushing unit in operation, the final product is conveyed to a 25,000 tonnes fine ore stockpile via a radial stacker. The fine ore is then manually reclaimed from the pile by front-end loaders and re-introduced onto the overland conveyor belt via a hopper.

The heap leach pad is a permanent facility employing a two-part liner system of a compacted layer of low permeability soil, with a 2 mm thick HPDE/LLDPE synthetic liner. The initial pad had a capacity of 15 Mt and sequential expansions to the pad are accommodating the total tonnage mined.

The leach cycle for oxide ore, based on test work, is 90 days; this will change for the higher lifts, since the solution return takes longer as the pad height keeps increasing. The sulphide ore is much slower leaching. Testwork indicates that it could take as long as 120 days without taking increasing pad heights into account. Solution application rate is about 5 to 8 L/h/m2 of crushed ore. There are three process ponds installed to contain the heap leach solutions. The pregnant solution pond has the live capacity of 8,600 m3, barren pond has 17,400 m3 and intermediate pond has 7,200 m3 capacities. There is an 8,600 m3 volume spare pond available as well. The process ponds have a double HDPE liner and fitted with leak detection pipes and pumps. The pond surfaces were covered with floating 100 mm diameter HDPE plastic balls in order to reduce evaporation.

The gold adsorption facility (ADR plant) consists of two trains of carbon columns with each train consisting of five columns. Gold from the heap solutions is loaded onto the activated carbon and the carbon is removed periodically for treatment. The gold is recovered from the carbon in a standard Zadra process consisting of pressure stripping, electro winning and smelting. The final product is a gold doré bar suitable for final processing to 99.999% purity in domestic or offshore refineries.