An itchy trigger finger might win you plenty of Yellow Coins or Hylian Rupees, but in the real world if you want some of that cold hard cash, better to hold off with all of those video games. Sealed copies of old cartridge classics are earning record sums at auction.

In the space of a few days, the record sum for a video game collectible has been shattered twice at auction, with bidding for the first time stretching into the millions of dollars. On Friday, a sealed cartridge of The Legend of Zelda sold for $870,000, blowing past the previous record of $660,000 set for a copy of Super Mario Bros. back in April. Then on Sunday, as the auction bonanza reached an unexpected climax, a sealed copy of Super Mario 64 sold for a whopping $1.56 million.

Retro video games are graded on the Wata scale, with experts evaluating the condition of their packaging and contents. The copy of The Legend of Zelda received a rating of 9.0 A, indicating a seal of above average condition, perhaps with light signs of scuffing. The value of this particular cartridge however lay in its rarity, as part of an early production run when the game was released to American and European audiences in 1987.

The first game in the iconic action adventure series, set in the fantasy land of Hyrule and starring the elfin protagonist Link, eventually The Legend of Zelda would sell over 6.5 million copies. Alongside Super Mario Bros., the original Zelda proved pivotal to the success of the Nintendo Entertainment System.

According to Heritage Auctions, who handled both sales, the rare copy of The Legend of Zelda was ‘the earliest sealed copy one could realistically hope to obtain’. In an effusive listing, the Dallas-based auction house called the ‘No Rev-A’ cartridge ‘the apotheosis of rarity, cultural significance, and collection centerpieces’. In short, for hardened video game collectors, this version of Zelda was a holy grail.

By contrast the record-setting copy of Super Mario 64 was graded 9.8 A++ by the experts at Wata, indicating near perfect condition. But the game itself, which saw Mario transition to three dimensions from its roots as a side-scrolling platformer, is not especially rare as many sealed copies date back to the time of its release in 1996.

Super Mario 64 was a groundbreaking game for Nintendo, and a benchmark in early 3D video gaming featuring a dynamic camera system and full 360-degree analogue control. Still as the first video game cartridge to sell for more than one million dollars, the extraordinary price jump has been met with some scepticism by long-time auction watchers and video game experts.