This is an undated obverse die trial of the regular with drapery seated liberty half struck in copper. Pollock lists it under 1839 since this is when the type started but it is likely that it was struck many years later.
The example illustrated above, courtesy of Heritage, is ex Mid-American 5/91, Heritage 10/91. A second example in copper and one in aluminum, minus the stars, was part of lot 2368 in Ira & Larry Goldberg Coins & Collectibles 6/04 sale. The aluminum piece is shown below.
Note: The genuineness of these pieces have been questioned so they were not assigned numbers in the new Judd book pending further analysis.