Legend has it that the all-seeing eye on the back of the dollar bill is a symbol of Freemasonry.

It’s not. But the persistence of that myth is one reason why the state’s Masons are spending 25 million of their own dollar bills to create a new Heritage Center in Bloomington, expected to open by the end of June.

Their goal is to showcase the group’s history and philosophy — not only to Masons, but all Minnesotans.

“It has been a long time since Masonry in Minnesota has had a real home for our institutional history, and a place where the public could come to learn about Masonry,” said Eric Neetenbeek, president and CEO of Minnesota Masonic Charities.

“If not now, when?”

Membership in fraternal groups is falling throughout the nation, and the Masons haven’t been spared. The Grand Lodge of Minnesota has about 12,000 members now, down from a peak of 70,000 in 1960.

“It’s a very ornate, detailed building,” said project manager Patrick Sims.

But the Masons are in good financial shape, Neetenbeek said, having benefited from “the extraordinary generosity from generations of Masons. We do have the ability to take on this project.”

The Masons claim 15 U.S. presidents as members, including George Washington, both Roosevelts and, most recently, Gerald Ford. Prominent Minnesota members have included James J. Hill, Hubert Humphrey and the Mayo brothers.

The focal points of the new 47,000-square-foot facility are the museum and library, said Keir Johnson, director of the Heritage Center.

“We’ve been collecting historic artifacts for years and didn’t really have a place to display them,” he said.

The center also includes a meeting room available for use by any Masonic lodge in the state and a 425-seat theater that can be rented by the public.

The theater will make use of more than 75 rare, century-old theatrical backdrops collected by the Minnesota Masons. Throughout the history of Masonry, storytelling in the lodges often has been done through theater, Johnson said.

The center is being built with a blend of materials and craftsmanship that’s rare these days, said several members of the contracting team from St. Louis Park-based Adolfson & Peterson. Marble floors, oak paneling, 20-foot ceilings and specially cast light fixtures are just some of the dazzling features of the building, designed by Trossen Wright Plutowski Architects of Robbinsdale.

“It’s a very ornate, detailed building,” said Patrick Sims, the project manager. “I’ve never done anything with this level of detail and finishes.”

In addition, several local artists have been commissioned to create art for the building. Sculptor Nick Legeros, perhaps best known for his sculpture of Star Tribune sports columnist Sid Hartman outside Target Center, is casting two 14-foot-high bronze entrance columns. Gaytee-Palmer Stained Glass is refurbishing a historic stained-glass window for the library, 18 feet high and 8 feet wide.

For an organization that uses the proofs and tools of architecture as metaphors for moral truth, designing a home for itself takes on an extra layer of meaning.

“We want this building to be something we’ll be proud of 100 years from now,” Johnson said.