The gold mineralization at the Aurora Gold Mine exhibits features analogous to mesothermal or “orogenic” gold deposits typified by Archaean deposits of the Abitibi region, Canada. Features characteristic of the gold mineralization at the Aurora Gold Mine include:
• A strong spatial association to large scale shear zones;
• Relative late timing during active compressional deformation;
• A strong spatial association to large scale shear zones;
• Formed during greenschist metamorphic conditions;
• Association with a propylitic-phyllic alteration assemblages; and
• Is principally hosted in quartz-ankerite pyrite veining.

Gold mineralization in the Golden Mile area is controlled by a series of northwest-southeast trending shear zones. These shear zones are orientated sub parallel to the dominant northwestsoutheast structural trend that occurs throughout the Aurora property. The shear zones contain a steep northwest-southeast trending foliation that formed during northeast southwest shortening.

The gold mineralization in the Golden Mile area is chiefly associated with quartz-ankerite veins containing minor pyrite and associated hydrothermal alteration. The auriferous veins form weak to moderate stockworks preferentially in competent lithologies outside the most intensely deformed and altered segments of the shear zones. The auriferous veins have undergone minor post formation deformation. The geometry of the auriferous stockworks is controlled by the geometry of the competent lithologies and the geometry of shear zones, or a combination of both.

The Aurora Gold mine area is divided into four major gold mineralization zones: Rory’s Knoll (includes Walcott Hill East), Aleck Hill (includes Aleck Hill North), Walcott Hill, and Mad Kiss (includes Mad Kiss West).

Open Pit Mining:

The open pit has a mine life of 13 years based on a total of 19.0 Mt of ore mined at an average grade of 2.74 g/t. Approximately 55% of the ore tonnes are sourced from Rory's Knoll, 30% from Aleck Hill, with the remainder coming from the Walcott Hill, Mad Kiss and North Aleck Hill satellite deposits. Mining activity over the near term will be focused on fresh rock ore at Rory's Knoll.

The Company was able to successfully smooth the mining rate over the LOM with an average total (waste plus ore) rate of 70,000 tpd over the next four years and there after maintained at a steady 30,000 tpd rate over the remaining LOM. The average strip ratio over the life of mine is 8.9 to 1. The Company is reviewing strategic bids from contract miners to handle the waste stripping requirements, which is envisioned to bea 3-year campaign. Contract mining will allow the Company to save on the capital expenditure of a fleet not required beyond this stripping campaign,and based on initial proposals, is suggestive of reduced mine operating unit costs.

Underground Mining:

Rory's Knoll:
The Optimized LOM plan demonstrates improved economics through accelerating selective underground mining of higher grade stopes concurrent with open pit operations. Following a two-year pre-production period, underground mining at Rory's Knoll is expected to be fully ramped up in year 2022. Long hole open stoping ("LHOS") will initially target higher grade material between the bottom of the pit from-240 metres below river level ("mRL") and -460 mRL. In 2023, the Crown Pillar will be blasted and mining will then transition to sublevel cave mining (SLC) for the remainder of the mine life at an estimated average mining rate of 4,700 tpd. An improved mine schedule is expected to provide supplemental feed from the other satellite deposits later in the mine life which resulted in Rory's Knoll underground mining becoming deeper by approximately 200 metres than what the previous 2017 Feasibility Study envisioned.

Accelerating underground development is also expected to provide an ideal platform to potentially upgrade and expand the underground resource, especially at East Walcott where limited historical drilling has produced exceptional results. Initial underground mine development will be conducted primarily by contract underground mining experts. An extensive training and development program will allow the transition to an underground workforce that is expected to be composed of approximately 80% Guyanese Nationals over the life of the underground operations.

Satellite Deposits – Mad Kiss & Aleck Hill:
The Mad Kiss underground contributes an estimated 107,00 ounces (0.6 Mt at an average grade of 5.18 g/t Au) to the overall Optimized LOM Plan. Mad Kiss is expected to be developed concurrently with the Rory's Knoll underground with initial production expected in 2019 and continuing through to 2021. Mad Kiss will be mined via longitudinal LHOS froma depth of about -10 mRL to about -400 mRL.

The Aleck Hill underground is expected to contribute 153,000 ounces (1.1 Mt at an average grade of 4.28 g/t Au) to the overall Optimized LOM Plan beginning in 2028 and continuing through to 2033. Aleck Hillwill be mined through acombination of transverse and LHOS from a depth of about -140 mRL to about -500 mRL.

Material from mining operations will feed an apron feeder - primary jaw crusher system, which will produce a crushed product size of approximately P80 of 150 mm.

Feed material is hauled to the run-of-mine (ROM) stockpile (19,000 tonne capacity) adjacent to the primary crushing station.

The grinding circuit, upon completion of the second phase of the expansion, will consist of a SAG mill, a ball mill and gravity concentrators operating in closed circuit with a hydrocyclone cluster. The grinding circuit will operate at a nominal throughput of 362 t/h (rock ore feed), and produce a final particle size P80 of 75µm. The existing SAG mill is 7.9m in diameter by 5.6m effective grinding length driven by a 5.5MW motor. A new ball mill and two XD-20 gravity concentrators will be added to the grinding circuit. The ball mill will be 5.5 m diameter by 10.7 m effective grinding length driven by a 5.0MW motor.

The hydrocyclone cluster classifies the feed slurry into ........