Arsenic: Trading
Why copper smelters treat arsenic as a penalty
What this tab covers How and where it is bought and sold: who buys and sells, exchanges and benchmarks, contract types, the big trading houses and how prices are discovered.There is no exchange. Arsenic trioxide and metal trade under bilateral contracts, with prices assessed by agencies such as Argus. For the copper industry, arsenic matters mainly as a penalty element. Smelters charge penalties on concentrates above set limits, and China bars copper ore above 0.5% arsenic. Traders route such material to smelters that accept it, such as Namibia's (Blas & Farchy, pdf p. 224). Tilton and Guzmán note that clean and dirty concentrate prices still move together, with penalties absorbing the gap (pdf p. 187).
Where it is bought (buyers)
- CCA and arsenic-acid makers in the US buy trioxide and acid, mainly from China, Morocco and Malaysia (USGS)
- Zinc refineries and glassmakers in Europe and Asia buy trioxide on term contracts
- GaAs and InGaAs crystal growers in Japan, Germany, China and the US buy 6N-7N metal from a few qualified refiners
Where it is sold (sellers)
- Peruvian, Chinese and Moroccan producers sell trioxide; Belgium is the main EU source (59% of EU sourcing, EU CRM 2023)
- Malaysia supplied 99% of US arsenic acid imports in 2021-24
- Chinese refiners supplied 95% of US arsenic metal imports in 2021-24
Exchanges and benchmarks
| Venue | Contract | Notes |
|---|---|---|
| None | No exchange contract | Arsenic is traded only in bilateral deals; MCX and other Indian venues do not list it |
Contract types
- Bilateral term contracts for trioxide and acid
- Spot lots of 99% metal priced against Argus assessments
- Qualified-supplier contracts for high-purity metal used in semiconductors
Top trading houses
- No major trading house is prominent; trade runs through producers, chemical distributors and specialist minor-metal merchants
How prices are discovered
- Argus assessment of 99% arsenic metal (US warehouse, Rotterdam)
- US Census import unit values for trioxide by origin
- Copper-concentrate arsenic penalties set in smelter negotiations