Kenneth Jay Lane, the designer and bon vivant who built a global business from glittering acts of unabashed deception, producing fake and junk jewelry — or, as he liked to say, tongue in cheek, “faque” and “junque” — has died at his home in Manhattan. He was 85.

Chris Sheppard, the executive vice president of Mr. Lane’s company, said Thursday that Mr. Lane had died overnight in his sleep. No cause was given.

“I myself am a fabulous fake,” Mr. Lane once said. The son of an automotive parts supplier from Detroit — or “Day-twah,” as he would pronounce it with a wink — he was indeed one of his own most striking creations.

He came to be regarded as the first American jewelry designer to make it not only acceptable but also chic to wear fake jewelry, and in reaching that plateau he transformed himself into a high-society, jet-setting businessman with a lifestyle that was anything but cheap.