Not a planchet (yet), because the edge has not been rolled. Planchets are prepared from blanks. Planchets are the next step in the manufacture of coins.
Copper plated steel core.
Lots of modern coinage blanks around the World are made from these metals, similar to the British One Penny and Two Pence coins, which are of copper plated steel, but have a lower weight to this example.
You can search numista, by putting a range of weights and diameters as search parameters. You may find some plausible possibilities, but that would probably fall short of proof. Tokens or other things could be made from blanks.