Black Sabbath’s self-titled debut album turned 50 years old this week. And in honor of that anniversary, Keith Macmillan, aka Keef, the artist who designed and photographed the mysterious album cover and the sleeves for Sabbath’s next three albums, agreed to be interviewed for the first time, discussing his early work for the band at length in a feature for Rolling Stone. “I’m very happy just to do this for Sabbath, really,” he says.

So who is the mysterious woman on the cover of Black Sabbath? Not a witch, as it turns out. In reality, it was Louisa Livingstone, a young 18- or 19-year-old model Macmillan picked out from a London modeling agency. “She was a fantastic model,” he says. “She was quite petite, very, very cooperative. I wanted someone petite because it just gave the landscape a bit more grandeur. It made everything else look big.”

Macmillan decided to conduct the shoot at the 15th-century Mapledurham Watermill in Oxfordshire, about an 80-minute drive from central London. “Nowadays it’s very much more modernized, beautified, and touristed,” he says. “Then, it was quite a run-down and quite spooky place. The undergrowth was quite thick and quite tangled, and it just had a kind of eerie feel to it.”

Macmillan used Kodak infrared aerochrome film, designed for aerial photographs, and did “a little bit of tweaking in the chemistry to get that slightly dark, surrealistic, evil kind of feeling to it.” And so, to capture infrared light for the film, he wanted to start the shoot as early as possible.

“I had to get up at about four o’clock in the morning, or something as ridiculously early as that,” Livingstone recalls. “It was absolutely freezing. I remember Keith rushing around with dry ice, throwing that into the pond nearby, and that didn’t seem to be working very well, so he was using a smoke machine. But it was just one of those very cold English mornings.”

Macmillan says he brought props including a taxidermy crow and a live black cat he borrowed from a friend, which he says Livingstone is holding in the photo. She doesn’t remember a cat, however, and says her hands are like that just because she was trying to keep warm. “I think it might just be the way my hands are there,” she says. “I’m sure I could remember if it was a cat.”

“When I saw the cover, I thought it was quite interesting, but I thought, ‘Well, that could be anybody,’ so it’s not like I got any kind of ego buzz out of it,” Livingstone adds. “But, yeah, I thought it was a very nice cover.” That said, “Black Sabbath is just not my kind of music,” she says. “I feel awful for saying it, because it’s probably not what people want to hear, but it isn’t particularly my kind of music. When I got the album, I gave it a listen and moved on.” Her favorite bands at the time included the Rolling Stones, Beatles, Cream, Traffic, and the Doors.

After the shoot, Livingstone returned to her career in modeling and acting. She appeared on the covers and in art for Fair Weather’s Beginning From An End (also shot by Macmillan) and Queen’s Jazz, worked at the National Theatre in London, and appeared in television and films. She went on to study at the Faculty Of Astrological Studies in London and now lives in Europe, where she makes electronic music under the name Indreba. “I’ve found it very therapeutic to make the music, but I’ve never done anything to try and sell it,” she says. “It seems like a very hard business to break into.”