JOHANNESBURG (miningweekly.com) – Strengthening transparency to reflect what natural resource extraction contributes towards improving lives and living is what the Johannesburg- and London-listed Gemfields mining company has implemented in Zambia, where it mines emeralds, and Mozambique, where it mines rubies.

Gemfields, headed by CEO Sean Gilbertson, shares greater natural resource wealth openness and accountability through a metric called the G-Factor, which highlights – very accessibly – the extent to which that mine down the road is creating value in the community and the country.

Gilbertson remains committed to the transparency provided by the G-Factor for Natural Resources and continues to encourage broader industry adoption so that host governments and their citizens can better assess the stewardship of their resources.

Zambia’s Extractive Industries Transparency Initiative coordinator Ian Mwiinga, when asked by Mining Weekly last year to explain what the 'G' stands for, replied: “It stands for government, governance, good practice and so much more.”

In 2024, Zambia became the first country in Africa to publish this metric, which moves away from documents of hundreds of pages and reports on a one-pager that provides statistics at a glance.

On Thursday, April 9, Gemfields published G-Factor figures for the ten-year period from 2016 to 2025 for Kagem emerald mine in Zambia and Montepuez Ruby Mining in Mozambique, with computations for its two key mining subsidiaries set out in fine detail.

Gemfields shares the G-Factor detail annually to promote greater transparency and accountability regarding the level of natural resource wealth shared with the host country’s government, whether that value originates from the mining, oil, gas, timber or fishing sectors. It is also an indicator of the efficiency of natural resources companies in converting those natural resources into funds for the host government

The openness reveals the percentage of natural resource revenue paid in as mineral royalties, corporation tax and, where the relevant government is a shareholder, dividends. Over the ten-year period, it had Kagem at 17% and Montepuez at 26%.

“Gemfields’ 2025 G-Factor for Natural Resources underscores how contributions to host nations vary with market and operating conditions,” Gilbertson pointed out.

Last year, Montepuez paid 23% of its revenue to the Mozambique government. Although total cash payments were lower than in prior years – reflecting reduced premium-ruby output, the postponed December ruby auction and illegal-mining intrusions – the proportional fiscal contribution remained strong.

At Kagem, the one-year G-Factor was just 6% for 2025, far below its long-term average, owing to the halt in mining operations from January to April. The stoppage was the result of competitor actions as well as the temporary 15% export tax on precious gemstones, which was lifted in March 2025.

With operations restarted and market conditions improving, Gilbertson expects Kagem’s G-Factor to trend back toward its long-term average of around 18%.

In addition to Kagem and Montepuez, Gemfields holds controlling interests in various other gemstone mining and prospecting licences in Zambia, Mozambique and Madagascar and the pioneering auction platform that the company provides ensures a supply of coloured gemstones to downstream markets.