Sometimes, even 53 carats of diamonds can be understated: Look closely at this pendant and you’ll see a subtle touch of pink within the magnificent stones. This elegant necklace, not surprisingly, ­surpassed its high estimate May 14 at Sotheby’s Magnificent Jewels and Noble Jewels auction in Geneva, selling for $2.39 million. According to Sotheby’s senior international jewelry ­specialist Daniela Mascetti, the piece—which features a detachable pendant with two marquise, one brilliant-cut light pink, two circular-cut, and one briolette diamond, all suspended from a graduated diamond rivière—is most likely one of a kind. There is no known designer, but Mascetti imagines that the wearer may have envisioned the necklace herself after looking in her own jewelry box. “The client probably owned the three major stones,” she says, referring to the pendant, “and wanted to wear t