Fastmarkets opens consultation on counterparty weighting in copper concentrates TC/RC index

Fastmarkets has observed a notable and sustained decline in traders’ buying activities of clean copper concentrates to be loaded within a 13-week window, with more buying activity extending to delivery periods one to four years out. This has happened because miners have locked in their materials in advance to capitalize in record-low TC/RCs, reducing near-term spot availabilities.

Additionally, Fastmarkets has noted a widening spread between its trader purchase and smelter purchase, with increased dispersion in trader-side data inputs over recent months. Market participants have provided feedback noting divergent pricing dynamics between copper concentrates with significant byproduct credits (such as gold and silver) and clean concentrates with limited precious metals content.

Traders and smelters typically transact at different TC/RC levels, and the index normalizes these differences to ensure that all inputs are assessed on a like‑for‑like basis. Once that normalization is complete, Fastmarkets determines where within the trader-smelter spectrum the final index value should sit. It is this second element that is the subject of this consultation.

Fastmarkets is seeking industry feedback on the following areas:

• Whether the current 50-50 weighting between the trader purchase and smelter purchase remains representative of spot market activity
• Views on alternative weighting approaches, such as weighting based on transaction volumes, liquidity or other market factors
• The volume and proportion of physical trades conducted within the 13-week spot assessment window by each counterparty type, including any observed shift toward forward purchasing for delivery periods beyond this window
• The impact of precious metals and byproduct credits on copper concentrate pricing, and whether this creates distinct pricing dynamics

Currently, Fastmarkets applies a fixed 50-50 weighting between the trader purchase and smelter purchase normalization in the final calculation of MB-CU-0287 Copper concentrates TC index, cif Asia Pacific, $/tonne and MB-CU-0288 Copper concentrates RC index, cif Asia Pacific, US cents/lb. As a result, the final published index reflects the straight average of these two counterparty purchase sides.

To clarify, this counterparty‑normalization and weighting step is separate from the contact‑side market weighting. After normalization, inputs are assigned to either the buy‑side or sell‑side sub index, with each sub index contributing 50% to the final index. This contact‑side weighting is not part of the open consultation.

The indices involved in this consultation are:

MB-CU-0287 Copper concentrates TC index, cif Asia Pacific, $/tonne
MB-CU-0288 Copper concentrates RC index, cif Asia Pacific, US cents/lb

Additionally, Fastmarkets wishes to clarify that under its existing methodology, data is normalized by brand and other attributes to ensure like-for-like comparisons. Fastmarkets reserves the right to request contracts and documentation before inclusion in the calculation and to exclude data that is incomplete, not fairly presented or does not meet methodology requirements. This includes copper concentrate transactions where byproduct credits or non-standard side-terms may affect pricing comparability.

Following this public feedback period, Fastmarkets may propose a change to its copper concentrates methodology. Any such proposed change would have a separate public feedback period ahead of a decision.

Please send your feedback by Friday March 5, 2026.

To provide feedback on this consultation, or if you would like to provide price information by becoming a data submitter to these prices, please contact pricing@fastmarkets.com and basemetals@fastmarkets.com. Please add the subject heading “re: Copper Concentrates TC/RC Index.”

Please indicate if comments are confidential. Fastmarkets will consider all comments received and will make comments not marked as confidential available upon request.

To see all Fastmarkets pricing methodology and specification documents, go to the Fastmarkets methodology page.