There's more to it than the metal. It has to have a certain weight, be compatible with vending machines, coin counters and what not. When the Mint has a metal analysis done they go through a wide variety of metals, weights, etc etc etc you may want to peruse this thread, download the US MINT document and read it. https://www.cointalk.com/threads/alternative-metals-testing-for-us-coinage.333055/
