Katy Perry on April 18, 2012 in Hollywood, California. Credit: Michael Tran/FilmMagic

Katy Perry's recent hair color switch-up to dark purple is by far the moodiest look the "Part of Me" singer has worked since her jet-black locks in early 2011.

"She wanted to go to a more dramatic, darker, almost punk rock Goth vibe," Perry's hair colorist, Rita Hazan, who owns the NYC-based salon Rita Hazan and has a line of hair products at Sephora, tells Us Weekly. "Her new color is what I call 'purple velvet' -- it's dark and rich."

The star debuted her new, multi-tonal look enhanced with several hair extensions at the Hennesy vs. DETAILS At Midnight party at Coachella April 13.

"Somehow in the middle of all this…I found time to change my hair color, finally. #ForeverWalkingPantonePalette," she tweeted the day before.

Hazan is the pro behind the star's cheery bubblegum pink hair color from October and her most recent bright blue hue, which she debuted two weeks after she ended her 14-month marriage to Russell Brand on Dec. 30.

To ensure that the color chameleon's hair stays healthy throughout her frequent dye jobs, Hazan shares her special hair-saving potions.

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"She uses the Rita Hazan Foaming Color Gloss ($26, sephora.com) to maintain the color's vibrancy and I mix a special conditioner with color for her to use every time she washes her hair," Hazan dishes.

Adds the hair pro, "I love creating colors for [Katy] because she always knows how to rock it!"