Kingsgate has received approval from the Thai Board of Investment to undertake a $100m expansion of its Chatree North gold processing plant.
The Australian gold miner, which has been working on the mine since 2001, will undertake the expansion through its Thai subsidiary Akara Mining.
The expansion will extend the life of the mine by ten years and increase ore processing capacity by five million tons a year.
Once expanded, gold production capacity at the plant will increase from 200,000oz to 250,000oz a year.
The company plans to raise the capital for the expansion though debt.