As we previously reported, last week a copy of Action Comics #1, Superman's first-ever appearance, became the first comic to reach the seven figure mark, selling for exactly $1m.
This was 10,000,000 times as much as it was first bought for back in 1938 (10c), in a sale which quashed any doubts as to comics' status as a major high-end collectible in 2010.
As if this wasn't enough, Action Comics #1 was surpassed only a few days later.
Detective Comics #27, the first-appearance of Superman's fellow crime-fighter Batman, then sold for $1,075,500 at Heritage.
This week has unquestionably been a historic one for the rare and collectible comic books market. But Detective Comics #27 wasn't the only big sale at Heritage's February 25 auction.
Second highest lot went to DC's rival, Marvel Comics - home of Iron Man, the Incredible Hulk and other superheroes.
The Marvel Comics #1 Pay Copy is one of the most famous single comics in the hobby. It can also be found in the Guinness Book of World Records, thanks to a 2001 sale of a copy reported at $350,000.
Of the few Marvel Comics #1's considered to be the very best of their kind, this edition is regarded as the very best thanks to its nicer spine and better centring (i.e. words like "The" or "Marvel" aren't cut-off at the page edges, or printed askew).
Superheroes included in its pages include Sub-Mariner, the Human Torch and Ka-Zar.
Purchased by the present owner for $205,000, this historically significant edition realised a final hammer price of $227,050 at the Thursday sale. Not quite $350,000, but still impressive nonetheless.