The Flintstones S06 E19 The Treasure of Sierra Madrock

"Yabba Dabba Doo!"

Two con artists posing as gold miners sell Fred and Barney phony mine. Wilma and Betty find out and trick the con artists into buying the mine back, but Fred and Barney, convinced of its value, won't sell. Only the threats of the con men convince them to recover their investment and head back home.