6,000 loyal customers of Sonny’s Diamonds & Jewelry, 100 Fillmore St., in Cherry Creek North, received an email earlier this week, saying the once venerable retailer is going out of business.

Sonny’s building lease is ending after nearly 30 years in business, and the owners said they were unsuccessful in finding a suitable new location.

Michael Nedler started the business with his father in the late 1970s. At the time, customers’ tastes trended toward black-tie affair showpieces and high-fashion jewelry.

Sonny’s will keep its doors open until it has liquidated its entire $4 million inventory. The skittish economy, which is taking a toll on luxury goods retailers like Neiman Marcus and Saks, factored into the decision to close Sonny’s, but apparently it wasn’t the principal reason.

In his 29 years, Nedler has seen “some pretty tough times,” though he added that Sonny’s never had an unprofitable year.

“It’s certainly as tough as I’ve ever seen it,” he said. “But the one thing in business that I’ve learned is appreciate the good years because they don’t last forever, but don’t despair with the bad because they don’t, either.”

Six Sonny’s employees will lose their jobs.

Liquidation begins today with a 2.6-carat yellow diamond set among 1.3 more carats of diamonds marked down to $46,400 from $58,000. A strand of Tahitian pearls is 70 percent off its $14,000 original price, and all Oris Swiss-made watches are 20 percent off.