SALMON, Idaho (Reuters) - The head of the company that owns the Idaho silver mine where a worker has been trapped underground for eight days said he still hopes rescuers will bring the miner safely home to his family.

"We have not given up hope," Phil Baker, the president and chief executive officer of Hecla Mining Co., said in a video message posted on the company's website on Saturday.

"There are many examples of miracles where people have managed to survive for extended periods of time under very difficult conditions."

The message came as crews neared the last -- and most dangerous -- stretch of blasting through solid rock as they worked to reach the site more than a mile below the surface where Larry Marek, 53, was trapped by a cave-in April 15 at the Lucky Friday Mine in Mullan.

No contact has been made with Marek, whose condition is unknown.

Cameras snaked through bore holes into an open area where Marek might have found refuge during the collapse have failed to capture any sign of a worker who Baker said was a resilient man and one of the company's best miners.

Fresh air and water have been pumped into the opening for several days.

Crews have advanced 184 feet through a 220-foot tunnel to the accident site in a drill-and-blast operation that began on Monday.

The company reported a setback on Saturday, when a long-distance probe near the cave-in detected rubble and sand instead of additional open area, according to a news release.

Rescuers drawing nearer to the unstable area where Marek was tapping a vein of silver must take additional precautions to ensure their safety and avoid injury to Marek.

Their plan, expected to slow the advance, calls for reinforcing the tunnel with metal frames, timbers and steel supports.

Marek, a 30-year veteran of the mining industry and 12-year employee of Hecla, comes from a family whose connection to mining goes back three generations, Baker said.

He said mines from across the globe have offered their expertise and resources for the search, which has placed on hold any inquiry into the cause of accident.

The eight-day, 24-hour rescue effort -- which Baker said was "almost superhuman" -- has galvanized the 850 residents of Mullan, where the Lucky Friday is the economic mainstay.

Mullan is one of seven towns in an historic mining district in Idaho known as the Silver Valley, which runs along the south fork of the Coeur d'Alene River near the state's border with Montana.

The Lucky Friday is one of three active silver mines in the United States owned by Hecla, which was founded in the Silver Valley and is based in Coeur d'Alene.

(Editing by James B. Kelleher and Jerry Norton)

Mochila insert follows.