After four years of sitting vacant, the Hansen Planetarium building soon will have a new tenant: Salt Lake City on Thursday announced that it is selling the building to jeweler O.C. Tanner with promises that its historic charm will be boosted by the deal.

The company will buy the building for $1.2 million with plans to relocate its Eagle Gate Tower store there as soon as possible, likely in two years or so.

"We've been looking for a couple of years for a permanent location, and the planetarium becoming available has caused us to think we could create a really unique and wonderful thing in Salt Lake," O.C. Tanner Chief Executive Officer Kent Murdock said Thursday. "It would be a great benefit to the city and a great benefit to us and our store."

The planetarium building, at 15 S. State, was built in 1904 to house the city's public library. It is listed on the National Register of Historic Places.

In 1968, an addition was built behind the historic mansion to house the Hansen Planetarium, which vacated the building in April 2003 when it was replaced by the Sheila M. Clark Planetarium at The Gateway.

Murdock said O.C. Tanner's plans are to demolish most of the planetarium annex and focus on the approximately 10,000-square-foot original building.

"We want to just bring everything back to the mansion," he said. "I think you'll see the building restored to its very, very beautiful original version."

The planetarium's internal dome, which is used for projecting light shows and other visual presentations, will be donated to the planned Zion's Gateway to the Stars planetarium in Orderville, Kane County.

Before the deal can be finalized, the city's Historic Landmark Commission must approve the plans. That likely will be discussed at a Sept. 5 meeting.

Murdock said the company has hired architects to work on the renovation, and they are making some changes based on 100-year-old photos of the original building.

The front stairs likely will be replaced by a more sweeping staircase to match the original, and the water fountain in front of the building — which, coincidentally, was donated by O.C. Tanner when the planetarium first opened — will be removed.

Salt Lake City property manager John P. Spencer said an administrative committee selected O.C. Tanner after reviewing two proposals and decided O.C. Tanner was best equipped to restore the building.

"They have the financial wherewithal to pull off what needs to be done," he said. "It would take $4 (million) to $5 million to bring the building up. Mechanicals are basically at the end of their life. Electrical, while fine, needed some work. And that doesn't include seismic work."