I finally added this elusive chip to my Sahara collection last month. It's listed in TCR as a "Q" value chip and sold for a couple of letters higher.

TCR lists two Nevada 60c chips. Name the other 60c chip and I'll send you an obsolete Aladdin "London Club" roulette chip from Las Vegas as a prize. For extra credit, explain why the casino had a 60c chip at all.