CHICAGO (CBS) — A Lakeview synagogue has unearthed a 3,000-pound mystery, and professional locksmiths are welcome to come and take a crack at it.

Plumbers found it while digging in the parking lot at the Anshe Emet Synagogue back in June when they found the massive safe buried in the ground.

“I’ve been in the trade for 30 years, and this is my first safe,” construction worker Russ Moen said.

It has become the talk of the construction site while crews work around it.

“Is there gold in there? Is there nothing in there?” Moen said. “You know, the old Al Capone theory, and talking about getting Geraldo out here.”

Jay Quinn, site superintendent for Bulley & Andrews construction said the safe proved to be a tempting find.

“A few of us were going to haul it off and not tell anybody, and split it up whatever we could find,” he said. “We thought better of it.”

Locksmiths and ‘safe-crackers’ have spent the last two weeks trying to drill, pry, and crack the safe open, with no luck.

Some longtime locksmiths said getting into the safe will be very tough because of its age, and because it’s so badly rusted. Experts said it likely was made around 1906.

The cost to open it could be upwards of $10,000 due to the special equipment and time it would take to crack the safe.

The synagogue plans to bring someone in over the next couple weeks to drill a hole in the safe first, and put a scope inside to find out if anything is inside. If it’s empty, they plan to preserve it, and possibly display it on the property.