Canadians from 1851 would be shook if they found out that a postage stamp they used to mail a letter now costs as much as a down payment on a home.

A rare Canadian stamp issued over 170 years ago was sold for $292,500 at an auction in Ottawa last weekend.

The 12-Penny Black

Called the 12-Penny Black, the stamp was the star of the show hosted by Sparks Auctions.

Considered to be in pristine condition with full original gum, it features a portrait of Queen Victoria and would’ve cost 12 pence, as it says on the stamp.

12-Penny Black courtesy of Sparks Auctions

According to the auction company's site, only 1,450 of these stamps were sold, and of those, only 17 were known to be mint singles with original gum.

Gum is a substance applied to the back of a stamp that helps it adhere to an envelope.

Why is it a big deal, and how does it make a stamp rare?

According to stamp auction house Brixton-Chrome Inc., that’s because "very few examples of stamps issued before 1900 have survived with completely undisturbed original gum."

Although the buyer's identity was not released, Sparks Auctions General Manager Peter MacDonald told CTV that the buyer said, "The sisters are united."

Meaning that the person who bought the 12-Penny Black also purchased the identical stamp that Sparks Auctions sold in 2017 for $327,000. That "sister" stamp was located just below this one on the sheet.

If you're a collector but don’t have that kind of money to buy one of Canada's rarest stamps, there are many collectors item coins that could be in your wallet.