In July, U.S. Senator Carl Levin also argued that a copper ETF would fuel speculative trades in the physical markets. [Senator Opposes Physical Copper ETFs]

J.P. Morgan and BlackRock, on the other hand, believe that the funds would be miniscule in size compared to the global market and that the investments would be used for smaller investors to gain exposure.

In the meantime, the average retail investor can gain access to copper price movements through fund products that hold copper futures contracts, such as the iPath Dow Jones UBS Copper Subindex Total Return ETN (NYSEArca: JJC), iPath Pure Beta Copper (NYSEArca: CUPM) and United States Copper Index (NYSEArca: CPER).

For more information on copper, visit our copper category.

Max Chen contributed to this article.