Heisey Whirlpool #1506 was produced 1938-1957. A major pressed tableware pattern made only in Crystal and Zircon. Most items are marked with the "Diamond H". In the later years the name was changed to Provincial. Special note: If the item color is not Crystal or Zircon then it was produced by Imperial.
Imperial Glass Corporation continued production under the Provincial name from 1957-1980 in a large array of colors. Some of the early production carried the "Diamond H" trademark.
