If you think tortoise-shell sunglasses are conservative and classic, you’re right. If you think tortoise-shell sunglasses are fab and fierce, you’re right again. That’s because torts, as they’re called in the eyewear biz, have never gone out of style. But the newest interpretations are so inventive, there’s a style for every fashion persona.

    “The beauty of tort is that it really goes with anything,” says Kristen McCabe, senior product manager for the luxury sunglasses purveyor Ilori. “It is more traditionally a female color, but that, too, is changing, [as] men are becoming more fashion-forward.”

    Marianne Kotzbauer, fashion buyer for Sunglass Hut, attributes tort’s heightened popularity to a vintage eyewear trend sported by many a celebrity. That trend includes round, square, cats-eye and oversized lenses, Wayfarers and its infinite variations and, of course, tortoise.

    “Also, some of the fashion colors for [summer] are bright, and there’s the safari look, and tortoise blends so well with those,” Kotzbauer says. “Sometimes black is a little harsh.”

    Actually, we’re not talking about genuine tortoise. The sea-faring hawksbill turtle, long hunted to turn its protective casing into dishes and fashion accessories, is a critically endangered species and protected by international law. In today’s vernacular, tortoise refers to a mottled coloration, usually in the brown family and almost always in plastic.

    The biggest news is color, and it comes in myriad variations. Most popular at Ilori, which recently opened its first Chicago-area store in Old Orchard, is the subtle layer of hue laminated inside the frame.

     “The most popular color is pink,” says McCabe. “Brown and pink is a classic color combo, but the cosmetic effects are so great by giving the skin a rosy glow without makeup.” Derek Lam’s cat-eyed “Marissa” ($320) and Blinde’s squared “Miss Delicious” ($255) models are two examples.

    Lenses, too, are washed in color, and gradients rather than solids are big, says Blake Kuwahara, creative director of Base Curve Eyewear in Sun Valley, California.

    “We’re also seeing double gradients: gray and violet, and blue and gray,” Kuwahara says. “The tortoise is the neutral, and we’re using lenses to introduce color.”

    Some designers stay within the traditional tort hues, but expand the spectrum to range from palest beige to almost black. Salt Optics created Yellow Jacket, a brown tort with flecks of brilliant yellow, available in several frames, including the Elise ($340).

    Other designers are combining tort with solids or metals. Fendi’s FS356 is an updated classic, with rectangular lenses and wide stems. It comes in three tort color schemes: dark brown, caramel and taupe, as well as black ($375). Ralph Lauren does wire-rims with tort stems in RL7012 ($210). John Varvatos does the opposite in V729, a mostly metal style with a thin line of tort around the lens ($340).

    And how about this variation on a theme? Ray-Ban Wayfarers ($140) in a new tort and black combo: tort stems and brow with black curving under the eye. (Wayfarers also come in red and white.)

    As for a frame’s thickness, Kuwahara compares them to hemlines. Both long and short skirts are in vogue, as are both thin and thick eyeglass frames.

    “Thicker frames are interesting because they make a bold statement,” Kuwahara says. “They speak to the material of tortoise because you see more of it. A thinner frame is more subtle, which can be very appealing.”

    One statement-maker is Carolina Herrera’s H735, which wraps round lenses in a triangular tort frame, thicker at the sides and thinner at the bridge of the nose ($350).

    Oversized frames are as ubiquitous as in seasons past, but glam is easing off a bit. You’ll still find huge logos and jeweled embellishments from the likes of Versace, Bulgari and Dolce and Gabbana, but less obvious accents such as laser etchings and filigree hardware are quickly stepping up.

    Kotzbauer reports that some designers are replacing logos with symbols that stand for something they are known for. Coco Chanel’s long and well-documented association with pearls and camellias, for instance, is replicated in certain Chanel frames rather than the noisier, chunky double-C’s.

    “The trend is going toward something a little more subtle, but there is still a customer who gets excited about embellishments,” Kotzbauer says.

    “We’re not selling a lot of what I consider bling,” says McCabe. “Our customer is looking for something more understated and refined.”

    That said, Ilori’s tortoise collection includes a limited edition by Tiffany and Co. “Tiffany Lace,” as it’s called, is an oval wrap featuring a sterling silver starburst embellishment with center diamond. It was inspired by one of Louis Comfort Tiffany’s tiara designs over 100 years ago. The price is $1,100.