I think the type 3 was actually the first issue. I believe that the yellow $2.50's came out before the $1 yellow chips. The type 3 matches an uncut web of 3 - $25's and 1 - $100 I picked up from the original person in charge of the brass core chips. The web is marked 2000 Hours / 6-15-72. I also found two silver core $25 chips from Harrah's. One belongs to a friend of mine and the other was bought from a third party. According to my Harrah's source, a total of 9 silver core chips were made.

-John