Margaret Crocker's great-great-granddaughter discovered the secret of a fleur-de-lis brooch that is the crown jewel of "Treasures, Curiosities & Secrets: The Crockers and the Gilded Age," opening Wednesday at the Crocker Art Museum.

"That was a wonderful moment," says 77-year-old Margaret Langford, who earlier this year delivered the brooch to the Sacramento institution her ancestors founded in the 1870s.

"We went on a tour of the museum with (chief curator) Scott Shields, and he took us up to the portrait of Margaret Crocker and said, 'Here is your great-great-grandmother.' We were looking at it and, all of a sudden, all of us saw that she was wearing the pin we had brought."

Until that moment, Langford believed it originally had belonged to one of Margaret Crocker's daughters.

"And then we realized it went back a whole generation," she says.

Langford came from Atlanta, Ga., to deliver three family brooches to the institution built by her great-great-grandparents, Margaret and Edwin Bryant Crocker. She and her brother, Rutherford Ellis Jr., had inherited them from their mother.

"When my mother was getting older, we talked about what we should do with the jewels," Langford says. "They're very ornate and large, and neither my brother nor I move in those circles. We talked about giving them to the Crocker Museum, so when she died I wrote out there to the museum and told them who I was and asked if they'd be interested."

Shields called the gift "pretty swell." Langford was unwilling to divulge the value of the pieces.

The brooches, all dating to the late 1800s, inspired the museum's staff to mount "Treasures, Curiosities & Secrets: The Crockers and the Gilded Age." It's the last major exhibition before the museum closes its doors in May for the move into its new $100 million wing. The reopening is set for Oct. 10.

The 100 or so items on display include a just-discovered pair of Margaret Crocker's magenta boots, plus furniture, apparel, china and other items that belonged to Sacramento's first family of art.

And then there are the brooches.

Margaret Crocker wore her diamond-and-opal pin for a sitting with portrait painter Frank M. Pebbles in 1887. She apparently bequeathed it to her daughter Jennie. The other two brooches, both by Tiffany & Co., were gifts to Jennie from her husband, Jacob Sloat Fassett: Medusa carved on amethyst and a bust of Marie Antoinette carved on aquamarine.

The three jaw-dropping brooches eventually came into the possession of Langford's mother, who often wore them for a night on the town.

"In that era, in the '30s and '40s, they dressed up a lot and went out for the evening. My mother kept the jewelry at the bank, and she'd get it out, and everybody would have a fit over it," Langford says.

She and her brother agreed that the jewels belonged at the Crocker Art Museum, and that gave her a reason to finally come see the place.

In 1873, the Crockers built what is now the oldest continually operating art museum west of the Mississippi River.

After her husband's death, Margaret Crocker presented their private gallery and art collection to the city of Sacramento and the California Museum Association, in trust for the public. The gift was made May 6, 1885, and celebrated with a community-wide Floral Festival in the matriarch's honor.

The Crockers were one of Sacramento's leading families during the Gilded Age, and one of its wealthiest, worth around $10 million in the late 1800s.

Edwin Crocker was a lawyer who served on the California Supreme Court and became legal counsel for the Central Pacific Railroad. He worked alongside Leland Stanford, Mark Hopkins, Collis P. Huntington and his brother Charles Crocker – the Big Four – who were key to expediting construction of the western half of the transcontinental railroad.

"There probably would have been a Big Five if E.B. had lived longer, but he died early," says Shields. "He really was instrumental in getting that railroad built and completed, and he did a lot more work than other members of the Big Four."

Call The Bee's Dixie Reid, (916) 321-1134.