Master of Reality is the third studio album by English heavy metal band Black Sabbath, released in the United Kingdom on 6 August 1971[4] by Vertigo Records.

It was certified double platinum by the Recording Industry Association of America (RIAA) after having sold over two million copies in the US.

[10] This was to be Bain's final collaboration with Black Sabbath as guitarist Tony Iommi took over production for the band's next several albums.

Drummer Bill Ward explained: "Previously, we didn't have a clue what to do in the studio, and relied heavily on Rodger.

Bereft even of reverb, leaving their sound as dry as old bones dug up from some desert burial plot, the finished music's brutish force would so alarm the critics they would punish Sabbath in print for being blatantly thuggish, purposefully mindless, creepy, and obnoxious.

Twenty years later groups like Smashing Pumpkins, Soundgarden, and, particularly, Nirvana, would excavate the same heaving lung sound ... And be rewarded with critical garlands."

Iommi believes the band might have become too comfortable, however, telling Guitar World in 1992, "During Master of Reality, we started getting more experimental and began taking too much time to record.

Osbourne had to sing really rapidly: "Rocket engines burning fuel so fast, up into the night sky they blast," quick words like that.

During the album's recording sessions, Osbourne brought Iommi a large joint which caused the guitarist to cough uncontrollably.

A fragment of Iommi's coughing was later added by producer Bain as the intro to "Sweet Leaf," a song which was admittedly an ode to marijuana use.

Writing in Mojo in 2013, Phil Alexander observed: "To most it is the quintessential stoner anthem, a point borne out by Sabbath's own Olympian consumption of hashish during their early days."

"[13] Butler, the band's primary lyricist, had a Catholic upbringing,[11] and the song "After Forever" focuses entirely on Christian themes.

At the time, Black Sabbath were suspected by some observers of being Satanists due to their dark sound, image, and lyrics.

[14] The first editions of Master of Reality came in an 'envelope sleeve' containing a poster of the band, and with the album's title embossed in black lettering, visible in relief.

"[27] Rolling Stone magazine's Lester Bangs described it as "monotonous" and hardly an improvement over its predecessor, although he found the lyrics more revealing because they offer "some answers to the dark cul-de-sacs of Paranoid.

[35] Billy Corgan, leader of the Smashing Pumpkins, considered Master of Reality the album that "spawned grunge".

Black Sabbath and especially Master of Reality was a huge influence of the 1990s stoner rock / Desert Rock scenes in the UK and the US, bands like Kyuss, Monster Magnet, Sleep, and Orange Goblin have cited Sabbath and Master of Reality as a defining album of that genre.

[37] In 2013, Sabbath biographer Mick Wall praised Iommi's "ability to incorporate more neat riffs and sudden unexpected time changes in one song than most bands would contemplate on an entire album."

Note that the timing of "Orchid" on revised US pressings is incorrect: it includes the "Step Up" introductory section of "Lord of This World."