I am just starting to collect. Have been thru all of the FAQ's but no clear answer to my question. Have 50 or so chips bought at Vegas Cashier's windows, and want to collect same grade. What EXACTLY is that type of CASINO chip made of? I'm looking for that weight, size, and heavy, slightly rubbery feel and non-plasticky sound that you get from a chip from a Vegas Casino like Hard Rock or Bally's, etc. I know it's likely clay composite, but what are they EXACTLY?

Thanks