I know of only five $2.50 chips made using the 'bimetal' material and the Plastic Molded Slug Core construction. This California chip is one, there are 3 from Hollywood Park, and there's the second issue Hyatt Lake Tahoe. Several Harrahs $2.50's were made with brass cores of course.

If you need this 2.50, here's an unused one for $12 delivered. It's discolored, as are all these chips due to the material used. If you like, I'll send along a copy of the (expired) Harrahs Design Patent sheet for this type chip.

Anybody know who inventor Joseph Garaventa was? I was unable to Google up anything other than that he was a hunter.