PONTIAC, MI -- There is no longer a dome atop the Pontiac Silverdome.

The crowds of Detroit Lions fans adorned in Honolulu blue no longer cheer in vain for the likes of Barry Sanders or Billy Simms.

All that remains at the former 1975-completed, 80,000-plus-seat Detroit Silverdome stadium is silence -- and nostalgia, which Plymouth-based RJM Auctioneers is selling online.

An official auction begins in mid-May, but stadium seating is already on sale. Seat backs start at $25 and prices range from $100 for a single seat to $365 for four adjoining seats.

Because of the importance of the no. 20 in Detroit Lions history -- the jersey number worn by greats Barry Sanders and Billy Simms -- individual no. 20 seats are selling at a premium, $175.

Want to take home that seat you sat in when Elvis Presley performed a New Year's Eve show in 1975? Do you have decades of of painful Detroit Lion memories created in the same Silverdome seat that you want to preserve for posterity?

Jim Passeno, the vice president of facilities for RJM Auctioneers, says they are taking special orders for specific seats and offering certificates of authenticity, complete with a swatch from the Silverdome roof.

Seat auction site

Hundreds are expected to visit the Silverdome between Friday and Saturday to pick up the first wave of seat purchases, Passeno said.

The auction company is in the process of arranging tours for prospective buyers to view other artifacts included in the May auction.

Nealy 600 photos of those items are available for viewing on the auction website, and include a "Home of the Super Bowl" sign from the 1982 NFL championship in Pontiac, turf maintenance machines, vending equipment, a "huge" Detroit Lions sign, the scoreboard from when the Detroit Pistons played there and multiple Pontiac Silverdome seating location signs.

The stadium has been without a roof since its current owners, Triple Properties, purposely collapsed it as part of renovation work it says it's doing at the Pontiac facility, where the Detroit Lions played from 1975 to 2001.

Triple Properties, which also owns the Penobscot Building and the State Savings Bank in downtown Detroit, bought the Silverdome for $583,000 in 2009.

MLive Detroit has left a message with the owner requesting an update on development plans and is awaiting a response.

Passeno says his employees haven't observed any major work underway.

"We're not really authorized to go into details on that," he said. "They're keeping that pretty close to the vest.

There is some minor work going on, "just in the parking lot and they're planting trees."