According to "The Chip Rack" this chip was used at Harrah's in Reno and Lake Tahoe in the 1980s. This type of mold is called a PMSC mold and is made with a brass core and plastic on the outside. The Chip Rack list it as an "E" value chip - worth $15-$19 in new condition. These chips had a very long run - in fact they just recently replaced the yellow $1 versions.

You can see the other Harrah's chips at:
http://www.silver-state-treasures.com/reno/nvhartho.htm