Everything about that link suggests slugged plastic.
- Aluminum case
- Cards
- Dice
- Rules on how to play hold'em. I'd bet $100 that their hand ranks use the Royal Flush as the best hand, instead of just Straight Flush that a Royal is.
- A "10" chip - which tells me they don't really know how chips work efficiently.
- Priced at less than 40¢ a chip, assuming the case, dice, and cards are free - which they aren't, so the price per chip is probably closer to 25¢ - the price point expected for stylish plastic chips.
Still, a nice looking plastic chip. It's far better than dice chips. It's just a shady dealer selling something as "clay" when it is not.