Christina O'Haver, The Union Democrat

construction laborer working on a futuristic, high-speed Internet link in downtown Sonora discovered a link to the past Tuesday.

Eberardo Rodriguez, of Moreno Valley, was trenching the asphalt at Green and Bradford streets, shoveling dirt with his digging bar, when he made the find: a dime-sized gold coin predating the Gold Rush and California statehood.

The $2.50 coin was minted in 1844 in Charlotte, N.C., the markings indicate.

According to the Numismatic Guaranty Corporation website, 11,622 Charlotte mint $2.50 coins were made that year.

The metal alone has a value of $195.01, according to the NGC. However, factors such as age, condition and origin of the coin also determine its value.

"That sounds like a whopper," Sonora resident and coin collector Gerald Howard said. "A special mintmark could make it very, very valuable."

Gary Carter, owner of DD's Antiques N Such in Jamestown, offered to buy the coin from Rodriguez for $300, but the construction worker declined to sell it.

Carter heard about the coin discovery while he was out to lunch Tuesday and visited the construction site to evaluate it. He determined the coin was "really worn down on both sides."

"If it was in excellent condition, it books for $900 and up," he said.

Sharon Marovich, chairwoman of the Tuolumne County Heritage Committee, heard about the coin when chatting with Kleven Construction Co. workers digging behind her workplace at the Tom Marovich law office.

She offhandedly asked if they'd found any gold while digging and they showed her the coin. She said she was "astounded."

"I thought it was fabulous," she said.

Marovich said downtown Sonora's streets weren't paved until around 1922 and, up until the 20th century, people panned for gold in the dirt streets.

Mine tailings were unloaded onto the roads to smooth them over and, when it rained, it wasn't uncommon for people to sift through them in search of gold, she said.

If the coin had been dropped in the street by then, the prospectors overlooked it.

"It sounds like someone who was here during the Gold Rush dropped that coin in the dirt street and either couldn't find it or didn't know that he or she had dropped it," Marovich said.

She said today's Green Street was likely a prominent road downtown - possibly lined with saloons - when Mexican gold miners settled in the area.

"For that fellow to find that … It just, to me, shows that history is all around us," Marovich said. "It reinforces to me the historic nature of Sonora. It's in our buildings. It's in our streets. It's just all over."