Stamp box directory

EKC stamp box: dates and marks

If the stamp box on the back of your real photo postcard carries this mark, the paper’s production window narrows the card’s date. A stamp box dates the paper, not the photograph — read the range below as “no earlier than,” and let a postmark set the latest possible date.

Standard mark

circa 1930s–1950

Sources disagree here: start year differs widely: 1930 (S6 detail page), 1939 (S5 chart), 1940 (S1/S2), 1945 (S3); we publish the widest defensible span. We show the consensus range rather than false precision.

A real photo postcard of the shaft thrown from the SS Grandcamp in the 1947 Texas City Disaster, captioned on the card with the date, from the Postcard Origins collection — A real photo card of a propeller shaft flung from the SS *Grandcamp* — captioned, on the card itself, “Shaft from Grandcamp, Texas City Disaster, April 16, 1947.”Scanned from the Postcard Origins collection

The EKC stamp box on the back of the same card — The EKC box on the back — for the Eastman Kodak Company — dates the paper to roughly the 1930s–1950. The subject sets the floor: the Texas City Disaster, the deadliest industrial accident in US history, killed at least 581 people when the *Grandcamp*’s ammonium-nitrate cargo exploded on April 16, 1947. A photograph of a fragment thrown by that blast cannot predate it, so the card is **1947–1950** — the box and the event closing on one another.From the collection

Ranges cross-checked across: the2Buds.com chart, as republished by Sports Collectors Daily, ‘Dating Vintage Real Photo Postcards’; SABR Baseball Cards Research Committee, ‘Dating and Authenticating Real Photo Postcards’ (2017); Postcards Everywhere collector chart (2010); Playle’s Directory of Stamp Boxes (playle.com, frozen reference; marketplace closed 2020); Playle’s detailed stamp-box directory pages (playle.com/realphoto/photoa.php, photod.php; image-keyed, contributor-verified; fetched 2026-07-18). Approximate by nature — see methodology.

All stamp boxes Dating wizard