Congrats are in order for Ozzy Osbourne, who just set new sales marks for a pair of his classic singles — "Crazy Train" and "Mr. Crowley."

"Crazy Train" is the bigger of the two. The song was initially certified as gold by the RIAA back in 2005, but has seen significant growth over the last 15 years, now being certified as 4 times platinum (which equates to 4 million units). The track was initially released on Sept. 20, 1980 as part of Ozzy's debut solo album, Blizzard of Ozz. A live version of the track would follow as part of the 1987 Tribute album saluting the brilliance of Ozzy's Randy Rhoads era.

Ozzy Osbourne, "Crazy Train"

As for "Mr. Crowley," it too was part of Ozzy's Blizzard of Ozz album. The song, which served as the second single, has been certified gold (for half a million units) by the RIAA.

Ozzy Osbourne, "Mr. Crowley"

Both tracks have remained essential tracks in Osbourne's catalog and helped to launch his solo career after his split from Black Sabbath. The Blizzard of Ozz album hit No. 21 on the Billboard 200 Album Chart and was certified as five-times platinum (for 5 million certified units) as of February 2019.

Osbourne released his twelfth studio album, Ordinary Man, back in February.

Black Sabbath Songs Ranked (Ozzy Osbourne Era)