The sale of the Ghaghoo production will be carried out in parallel with the sale of diamonds recovered at Letšeng.
Gem Diamonds said that work is underway in the first four production tunnels within the kimberlite on Level 1 and the treatment plant is being revamped in preparation for full production.
Trial stope on Level 0 prepared for training purposes, the major ingress of water is managed and final sealing operations are underway.
For the period 1 July to 30 September 2014, the Letšeng project recovered 28,365 carats with an average value of $2,603 per carat.
The company has sold a 197.6 carat diamond, which was recovered at the mine in July, for $10.6m.
Gem Diamonds CEO Clifford Elphick said: "The official opening of the Ghaghoo mine was an important milestone for the Company.
"We are pleased to have completed the construction of the mine on time and within budget and to have overcome the challenges posed by developing a decline through some 80 meters of sand."
The company has started upgrade project on the Plant 2 Phase 1 upgrade, which is scheduled to be completed in the first quarter of 2015.
The project is designed to increase treatment capacity of the plant by 250,000 tons a year as well as reduce diamond damage
Further phases of the Plant II upgrade will be planned after the completion of Phase I.
