Psychedelic rock band Coven 1969 debut album Witchcraft Destroys Minds & Reaps Souls cover had a picture of two of the band’s members doing the Devil’s Horns hand gesture, more popularly knows as the Sign of the Horns in the Rock world.
Coven is recognized as introducing the Signs of the Horns to rock culture. The band openly used other Satanic symbols such as inverted crosses and popular Satanic slogan such as Hail Satan (Ave Satanas).
Tracks on their first album include: Black Sabbath, Pact with Lucifer, Dignitaries of Hell, and Satanic Mass.
Other bands and musicians helped popularized the Devil’s Horns such as Black Sabbath’s Ronnie James Dio, and KISS’ Gene Simmons.
Coven on wiki.
Coven’s Witchcraft Destroys Minds & Reaps Souls (Full Album, 45 minutes)