A sulphuric acid shortage is emerging as a restraint on Zambia’s copper growth, with Jubilee Metals Group (LSE:JLP) reporting a more than 200% increase in acid costs during Q4 FY26.
Shanghai Metals Market (SMM) reports that Ministry of Mines data show national copper production rising slightly 0.45% year-on-year to 447,181 tonnes in H1 2026. Meanwhile, small-scale copper production fell 35.2%.
The Ministry of Mines attributed the small-scale decline partly to inadequate domestic sulphuric acid supply and the delayed end of the rainy season.
SMM says recent company disclosures add a more immediate operating signal. Jubilee Metals reported that domestic acid availability in Zambia was largely reduced during Q4 FY26.
At the same time, acid costs have risen by more than 200%, with diesel increasing by 90%.
Jubilee Metals says these conditions had a marked impact on production at its Sable refinery and contributed to temporary closures among some metal processors in its operating area.
In FY26, Sable produced 1,207 tonnes of copper cathode, up 17.5% from 1,027 tonnes in the previous financial year.
However, the quarterly profile weakened towards year-end — cathode output increased from 217 tonnes in Q1 to 379 tonnes in Q3, before falling again to 250 tonnes in Q4.
SMM reports Q4 production was about 31% below Q3 and 34% below the Q2 peak.
A broader supply chain vulnerability
The developments in Zambia provide a real-world example of the broader supply chain vulnerability of the global sulphuric acid shortage, as Mining.com.au previously reported.
While the earlier disruptions were largely framed around tightening international supplies and rising costs across critical minerals, Zambia shows how those pressures can filter through to the mine and processing plant.
The issue is particularly significant for copper, where sulphuric acid is a critical input for processing oxide ores. In Zambia, tighter domestic availability is now emerging as a constraint on refiners and small producers, showing that the impact of the chemical shortage is no longer confined to international commodity markets.
For the broader copper sector, the situation outlines a critical distinction that having sufficient copper resources does not mean having the processing capacity or inputs required to turn those resources into saleable metal.
That distinction could become important as miners and developers look to expand copper production. Access to reliable processing inputs has become another factor in the viability and timing of new projects.
Zambia’s experience also highlights that production capacity does not necessarily translate into security of supply, particularly where sulphuric acid is largely consumed by integrated operations and smaller producers rely on the merchant market.
Impacts are not homogeneous
The impact of tight sulphuric acid supply is not homogeneous. According to SMM, large integrated operations with captive smelting and acid production are less exposed to the merchant market than smaller leach operators and independent processors.
First Quantum (TSX:FM) highlights this difference. The company’s Kansanshi mine generated 1.1 million tonnes of sulphuric acid in 2025 — almost all of which was consumed onsite in leaching circuits for cathode production.
Following smelter expansion, Acid Plant 5 could generate supplementary acid for internal use or external sale. However, this is dependent on mine geology and processing requirements.
SMM says this means that Zambia could be a key acid producer and still have a shortage in the merchant market. Installed acid capacity is not the same as freely available supply.
Jubilee Metals’ production mix also shows why copper growth is not only a mining issue. Combined copper units from the Roan and Molefe operations reached 3,739 tonnes in FY26, representing a 225% increase year-on-year.
Total production at Roan increased 145.5% alone, totalling 2,823 tonnes.
However, final copper products produced for sale only increased 1.3%, while Sable cathode production rose 17.5%.
SMM highlights that part of this gap reflects the build-up of oxide concentrate fines awaiting processing through Roan’s newly commissioned dewatering circuit and the fact that Jubilee reports different streams at different stages of the value chain.
Sulphuric acid outlook
Through the rest of this year, sulphuric acid availability is likely to remain an important variable for Zambia’s oxide and mixed-ore copper producers.
A March export-permit system could help retain more acid for domestic users, although SMM says it may not create additional supply.
In the near-term, the market balance will depend on smelter operating rates and internal acid consumption at integrated mines. Another key contributor is the surplus product that producers are willing and able to release into the merchant market.
Meanwhile for smaller leach operators, delivered availability and price could, therefore, remain more important than Zambia’s headline installed acid capacity.
Looking ahead to 2027, the acid balance could become an important differentiator between integrated and merchant-dependent producers.
A sustained improvement in smelter uptime, additional third-party acid sales, and effective domestic allocation could allow smaller mines and independent processors to recover output and participate more fully in Zambia’s copper-growth cycle, SMM reports.
However, SMM further notes that if the market remains tight, production growth is more likely to remain concentrated among large integrated operators that can secure acid internally.
Key indicators to watch will be merchant acid prices, smelter operating rates, export-permit flows, third-party acid sales, and Sable’s ability to convert rising upstream feed into saleable copper products.
Write to Aaliyah Rogan at Mining.com.au
Main image: Jubilee Metals
