Hummingbird said drilling had been focused on a resource definition at the Gonka deposit and some follow up drilling at the Komana West deposit. It will now focus on converting resources to reserves before eventually extending Yanfolila's mine life.
Despite originally planning to drill around 50,000m, the company drilled 23,697m due to the schedule becoming more targeted and being adapted to fit with the updated life of mine plan.
The drilling included 6,206m of reverse circulation (RC) drilling and 9,908m of diamond drilling at Gonka, 3,091m of RC and 2,536m of diamond at Komana West and 1,956m of RC at Guirin West.
Highlights from the drill results from Gonka were 15m at 16.03g/t from 207m depth; 20.05m at 4.63g/t from 118m depth; 11m at 4.11g/t from 79m depth; 14m at 3.88g/t from 178m depth; and 13.6m at 2.56g/t from 34m depth.
"This second batch of results delivers further positive results from those announced in September and shows the high-grade potential at Gonka owing to the significant numbers of wide and high-grade drill intercepts encountered to date," Hummingbird said.
At Komana West, a highlight was 15m at 4.25g/t from 8m depth, while at the Komana West South Extension the best interception was 12m at 1.9g/t from 90m depth.
The company said the additional drilling at Komana West had been useful to the mining operations, as the newly-drilled zones have been found outside the resource model and positive results had been found inside the current pit shell, increasing the amount of mineable ore available.
Chief geologist Murray Paterson said after analysing the drill results, the company was confident it was on target to increase Yanfolila's mine life.
"In light of these results, the exploration team on site is now working diligently to build a mineable resource that will aim to add more openpit and underground ore extending the current mine life," he said.
Yanfolila has a current indicated and inferred mineral resource of 22 million tonnes at an average grade of 2.54g/t gold for 1.8 million ounces of contained gold.
He added that drilling to date had been quite shallow, focussing on infilling the openpit resources, but attention would now turn to drilling out the underground resources at Gonka.
Paterson noted that Gold Fields had previously drilled Gonka and discovered high grades and wider intervals.
The company has scheduled mining planning work to start in February by CSA Global - Perth to prepare an underground mine design and schedule on the existing Indicated resources beneath the pit.