Joan Irvine Smith Unveils Her Homage to a Bygone Era : Art: Real-estate heiress gives a preview of her Irvine Museum with an exhibit of paintings that recall the Orange County of her youth.

After making headlines with her multimillion-dollar art-buying spree last year, real-estate heiress Joan Irvine Smith on Wednesday gave a preview of the Irvine Museum she has established to exhibit the bucolic California Impressionist paintings that remind her of the undeveloped Orange County of her youth.

“I can see (in the paintings) a California as we will never see it again--California as it was when I was a child,” Smith said.

The 4,000-square-foot private, nonprofit museum, on the 12th floor of an office tower here at 18881 Von Karman Ave., opens to the public today. Allowing for the exhibition of about 60 paintings at a time, tops, it will serve as a temporary site for five or six years until a larger, permanent museum is built in Irvine, officials said.

Smith said she has given more than $3 million in cash and paintings to the Irvine Museum but has not established an operating, acquisitions or donations budget for the future. She said she plans to solicit the private sector for money to run, acquire land for and build a permanent museum.

Smith, an arts patron and the great-granddaughter of James Irvine, who established the giant Irvine Co. real estate and development firm, received $250 million from the 1991 sale of stock in the company. That fall, she began voraciously snatching up California Impressionists paintings.

Smith said Wednesday she has amassed about 2,000 works but would not say how much she has spent. Various figures have been bandied about; one art expert who wished to remain anonymous said her outlay was well over $15 million. In the spring, she also plans to open a commercial gallery of California Impressionism and contemporary art.

The Irvine Museum, dedicated to the preservation and display of historical California Impressionism, will focus on works by plein-air painters, active between 1890 and 1930. Most depicted the Southland’s pristine landscape, emulating the French Impressionists and their adulation of natural light.

Currently, the museum’s permanent collection consists of about 65 paintings, but that figure will grow, officials said. All but one have been donated or paid for by Smith or her mother, Athalie R. Clarke, who also sits on the museum’s seven-member board.

The inaugural exhibit consists of more than 50 works from the permanent collection. Eventually, works on loan from other museums and elsewhere will be shown.

The museum will be open Tuesdays through Saturdays, 11 a.m. to 5 p.m. Admission is free.