12c Black, Plate 3 (36B).
Four, three affixed slightly overlapping and may have come from a strip, fourth with faulty corner, tied by red grids, "N. York Br. Pkt. 38 Jun. 6" credit datestamp on 1860 blue folded cover with three flaps to London, England,
ms. "P. Persia",
London datestamp of June 16, Fine double-rate use, this is listed by the U.S. Philatelic Classics Society
as the earliest known overseas use of Scott 36B,
the Scott Catalogue lists June 1 as the overall earliest known use (22x domestic rate cover from New York to Philadelphia)
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