FOR MARTIN KATZ'S CLIENTS, LEARNING THE BASICS OF BANGLES and baubles is child's play. Take Madonna's 16-month-old daughter, Lourdes, for example. On Jan. 17, the day before the Golden Globe Awards, Katz was asked to bring a selection of his vintage and new jewelry to the Material Girl's L.A. home. "I saw that the dress had a Gothic feel," says Katz of the black Balenciaga the star was set to wear, "so we wanted something of the period." As Madonna modeled an antique gold-and-cabochon-garnet earring and necklace set valued at $10,000, Lourdes toyed with a Cartier ruby ring. "Say Car-tee-ay," Madonna instructed the toddler. "No!" Katz corrected. "Say Mar-tin!"

And see Martin too. After all, a visit with the urbane 42-year-old jeweler has become almost de rigueur for a star prepping for a big event. In addition to Madonna, Kate Winslet, Jennifer Aniston and Christine Lahti all wore Katz loaners to the Globes. Others, like Nicolas Cage and Chris O'Donnell, don't just borrow, they buy. ER's Eriq La Salle is pondering a 2-plus-carat Asscher-cut diamond from Katz for fiancée Angela Johnson. "Martin is wonderful to work with," says La Salle. "He's a gem."

He certainly has the right setting: a posh, three-bedroom Beverly Hills penthouse apartment-showroom with a panoramic view of the snowcapped San Gabriel mountains and a modern art collection boasting a Picasso and a Hockney. Trying on pricey bibelots at a marble-topped "jewelry bar," celebs sip iced tequila, Dom Pérignon or mineral water while admiring themselves in floor-to-ceiling mirrors. "You expect to see Fred and Ginger pop out from behind the grand piano," says faithful customer Jennifer Tilly. "I feel like I have to have this jewelry, even if it means doing a bad miniseries."

Katz too has long appreciated life's finer things. The second youngest of five children of Aaron, owner of a laundry-equipment business, and Bert, a homemaker, Katz fondly recalls his bimonthly trips from his South Bend, Ind., home to Chicago, where an aunt worked for Laykin et Cie jewelers. "I was fascinated with gems and diamonds," Katz says, "but I had no clue what they meant."

He found out they meant a lucrative sideline while studying psychology and business at Indiana University in Bloomington. "I'd go to dorms with a shoebox and sell puka-shell necklaces, liquid silver and turquoise," he says. "My average piece cost $4."

After graduating in 1978, Katz headed to California and Laykin et Cie's L.A. branch. "I made $5 an hour and a tiny commission," Katz says. "I loved it." He managed the firm's San Francisco branch for six years before going solo in 1987. Although celebs now make up about 20 percent of his clientele, Katz says that private collectors are bigger spenders. (His top sale was a $2 million emerald-and-diamond necklace.) Katz, who designs some of his pieces, finds additional stock on trips to Europe and through estate sales. "The great unknown jewelry is hidden in safe-deposit boxes all over the country," he says. "It doesn't fit the heir's lifestyle."

But it fits Katz's. Never married, he enjoys the trappings of success—a '98 Porsche, jaunts to exotic locales like Botswana and the Philippines—and looks forward to sharing them with a special somebody. "I haven't been able to give anyone the right amount of time," he says. "But now more than ever I'd like to meet someone."

Until he does, Katz is happily hitched to his business, on call 24 hours a day to his charmed—if occasionally challenged—clientele. One morning last year he went to Courtney Love's L.A. house to pick up the necklace she had worn to the '97 Golden Globes the evening before. Still bleary-eyed, Love greeted Katz wearing the $285,000, 67-carat diamond creation. "I'm glad you came by," she said. "I didn't know how to get it off, so I had to sleep in it."

BETH KARLIN
ANNE-MARIE OTEY in Los Angeles

  • Contributors:
  • Anne-Marie Otey.