Here's an alternative to the usual rare rectangular postage stamps: a circular-shaped Alexandria, District of Columbia (or Virginia) 5c Black.

It is estimated at $75,000-100,000 and will auction from the Frelinghuysen Collection in New York on March 28.

The rare philatelic specimen is one of just six recorded examples. It is described as "very fine" by the auctioneer, and is printed on buff paper.

Three of the six known Alexandria, District of Columbia (or Virginia) 5c Blacks are Type I. The other three, including this one, are Type II.

The Alexandria, District of Columbia (or Virginia) 5c Black

As with all of the other recorded stamps of its type, this specimen was cut in a distinctive circular shape. It is uncancelled, and without its adhesive gum.

Billed as "one of the great rarities of United States philately," this Alexandria, District of Columbia (or Virginia) 5c Black hasn't appeared on the market since the legendary Ferrary sale of 1922.

An autograph on the stamp's reverse offers clues to its provenance. It has been signed on the back by Leonidas W Durbin: "L. W. Durbin/July 1879". Durbin was the Philadelphia stamp dealer who bought this stamp from the man who discovered it in July 1879.

Catalogue values gauge an unused Type II's worth at $100,000. This ought to prove realistic when eager bidders are unleashed upon the stamp on March 28.

We have several investment-grade postage stamps currently in stock. Click here to view.