TORONTO (miningweekly.com) – Canadian gold producer Banro has lifted the compliant reserve base at its flagship Twangiza mine, in the Democratic Republic of Congo (DRC), by 59% and extended the mine life to 14 years.

The TSX- and NYSE MKT-listed miner exploited the 210-km-long Twangiza-Namoya gold belt, in the South Kivu and Maniema provinces of the western DRC, where its four core projects comprised Twangiza, Namoya, Lugushwa and Kamituga.

Last year, the company had scaled down its exploration activities at all four projects and focused its geological expertise on supporting the production growth at Twangiza, development at the Namoya and identifying near-mine, high-grade targets.

Banro reported that the Twangiza proven and probable reserves increased 59% to 1.64-million ounces of gold, contained in 22.38-million tonnes of ore, grading 2.28 g/t gold, and included nonoxide materials in the reserve pit shell, which had been proven economically treatable with the existing plant.

This expanded the Twangiza mine life using the existing plant to 14 years.

At the company’s second operating mine, Namoya, the proven and probable mineral reserves had fallen 5% to 1.27-million ounces, contained in 20.53-million tonnes, grading 1.92 g/t gold, mainly owing to depletion.

Banro's consolidated mineral reserves grew by 23% to 2.91-million ounces, contained in 42.91-million tonnes of ore, grading 2.11 g/t gold at a gold price of $1 200/oz.

The company’s measured and indicated resources for all of its properties stood at 7.73-million ounces, comprising 154.91-million tonnes at 1.55 g/t gold, and 5.26-million ounces in the inferred category.

''The reserve growth at Twangiza has been achieved through the proven ability of the current plant to economically process nonoxide materials existing within the reserve pit shell. This achievement will extend the mine life of the current installed operations to 14 years and provide a foundation for future optimisation and the possible future expansion of the existing Twangiza operations,'' Banro CEO and president John Clarke said on Monday.

Meanwhile, Banro was planning exploration work at several targets this year to consolidate its position. Small teams would focus on generating new oxide targets in Lugushwa and Kamituga. At Namoya, exploration-drilling activities would be focused on near-mine resource upgrade and resource generation activities.

The main goal was to upgrade inferred resources within the Namoya Summit-Filon B reserve pit into a higher confidence resource, before converting into mineral reserves. Another objective was to define additional near mine oxide resources within 5 km of the run-of-mine pad. At Twangiza, delineation drilling would focus on near-mine oxide-resources generation on the Twangiza East and West mineralisation.

Together, Twangiza and Namoya produced 45 197 oz of gold in the period ended March 31.