No, it's not plastic: it is real copper, but made from a very thin plate. This is the reason for the "plastic like" sound when you nest it on another cup or slam it on the table. This is also why these chop cups are so cheap, and this is why they dent easily when they fall off the table.

If you own a straight Uday set of cups and balls, you will notice that this cup has the same size but is much heavier, due to the gimmick, than non gimmicked cups(that's why I don't recommend to buy the Uday combos, like most combos, either!).

The gimmick makes the balancing (hence the handling) not so good. I'd recommend to buy for a little more money the Ickle Pickle wide mouth chop cup or the large morrissey cup (both are very good chop cups, handle bigger loads are and excellent deals at Penguin!)

In the first moment it looks like a real copper cup, it feels cold and the weight seems also ok, but stop, there is something wrong. The sound if you put two of them together is completly different from real copper cups, because it´s not made from solid copper. The cup sounds like a copper plated or painted plastic cup. And I think because it is a copper plated plastic cup. But if you don´t reveal this secret to the audience, they won´t notice that fact.
The rest is ok, the magnet is strong enough, the handling is also ok. I just hope that the copper finish will hold and not peel off from the cup.