Ralph, according to the Herz Guide to USPC checks & chips these are from Detroit, circa 1930. The Guide lists 8 colors all with no denomination: red, white, brown, pink, lt. green, lt. blue, gray, & yellow. These aren't listed in Hertel's Illegal Guide. Home game? Whatever... nice chips!

Rich Hanover and / or Robt. Eisenstadt may have more info. on their web sites.

Dave Smith in New Hampshire
"LIVE FREE OR DIE"