ROI-Copper concentrate pricing slips into the shadows: Andy Home

Copper's bull ​narrative rests on the premise that the world's mines cannot supply enough of the red metal to ​meet the surging demand from both the energy transition and AI revolutions. Smelter treatment ‌and ​refining charges (TC/RCs) have historically provided a way of gauging the degree of mine shortfall.

High TC/RCs indicate a well-supplied copper concentrates market, while low charges signal raw material stress. It follows that when spot TC/RCs turn negative, as they have this year, the market is experiencing an unprecedented shortfall.

But there are two problems with this simple extrapolation. Firstly, like ‌any market indicator, TC/RCs reflect both supply and demand. China has built too many smelters too quickly, which is as important a price driver as global mine output.

Secondly, once TC/RCs turn negative, they are no longer a reliable indicator of what is really going on in the copper concentrates market. BEYOND THE HEADLINES

Recent spot tenders for copper concentrates have gone for head-scratching numbers. Reuters has reported that Chilean producer Antofagasta secured a negative treatment charge of $310 per metric ton for 10,000 tons of concentrates ‌from its Centinela mine.

Canada's Teck Resources has sold raw material from its Highland Valley mine at an even lower number, somewhere in the minus $370s. On the surface, it appears that smelters are now paying miners significant amounts of ‌money for the privilege of processing their concentrates.

This doesn't make sense. Otherwise, just about every smelter, particularly those without their own integrated mines, would quickly go out of business. Rather, smelters are monetising by-products such as the gold and silver contained in the concentrates and the sulfur generated in the smelting process.

Copper concentrate pricing has always been more complex than suggested by headline TC/RCs. The full payable price can be tweaked depending on quotational periods, by-product credits and penalties for impurities such as arsenic. All these components are now being fully flexed to preserve smelter margins.

Even the standard ⁠copper payable ratio ​of 96.5% is being adjusted in some cases, while other ⁠deals are thought to include refined metal and sulfuric acid buy-backs. The devil is increasingly in the detail of the multiple side-terms, which vary according to each smelter's processing profile.

"We put a huge amount of focus on headline treatment charges, but increasingly those headline levels seem like the tip ⁠of an iceberg with a huge mass of information under the surface," according to Albert Mackenzie, copper analyst at Benchmark Mineral Intelligence. BEYOND THE BENCHMARK

As headline TC/RCs fall ever deeper into negative territory and spot terms become ever more bespoke, what is to become ​of the annual benchmark? The benchmark is the reference price for the largest volume of concentrates in any one year, and there are signs that it is already starting to fragment.

This year's headline terms, negotiated ⁠between Antofagasta and Chinese smelters, were set at zero, down from $21.25 per ton and 2.5 cents per lb in 2025. But it's unclear how many others used the benchmark in their annual supply contracts.

Japanese smelters in particular baulked at the concept of a zero treatment charge. JX Advanced Metals said in ⁠February ​that "we believe we are securing slightly better levels than those Chinese smelters have reportedly agreed."

What those terms were exactly remains unknown since the company said it wouldn't comment on "individual cases." Sumitomo Metal Mining only confirmed in August that it had secured 2026 terms in "the double-digit range". It too declined to disclose exact figures.

INTO THE SHADOWS Negotiations on next year's benchmark have already begun, but don't expect much transparency any time soon.

Benchmark's Mackenzie notes, "This is a time of massive intrigue ⁠and uncertainty in the concentrates market," but warns that "headline treatment terms, which should be one of the guiding stars, are increasingly hard to read and understand". Given how much attention the copper market pays to mined output and ⁠the stresses in the raw materials supply chain, this poses a ⁠challenge to our collective understanding of a metal everyone agrees is going to grow ever more critical in our modern high-tech world.

(The opinions expressed here are those of Andy Home, a columnist for Reuters.) Enjoying this column? Check out Reuters Open Interest (ROI), your essential new source for global financial commentary. Follow ROI on LinkedIn, and X.

And listen to ‌the Morning Bid daily podcast on ‌Apple, Spotify, or the Reuters app. Subscribe to hear Reuters journalists discuss the biggest news in markets and finance seven days ​a week. (Writing by Andy Home; Editing by Marguerita Choy)