I saw a man walking along the beach with two kids I assumed were his son and daughter. He had a metal detector in one hand and was sweeping it back and forth as they walked along. I secretly hoped he would find something as I watched and, a few feet away from where I was sitting, his detector beeped.
He checked the spot a few times and, as the machine beeped to his satisfaction, he began digging with a strange scoop that was covered with holes to let the sand out. After every few scoops he checked the hole again with the detector to see if he had reached his fabulous wealth yet. Finally, when the machine stopped beeping in the hole, he used it to find where it was hiding in the pile of sand.
He did more digging, and finally found something. At first, I thought it was an enormous oyster, but (after the man washed it in the bay) it turned out to be a big, thin, triangular, grey-black rock. The man held the rock under the detector a few times and discovered it caused the machine to beep. It must have had some iron ore in it (or another ore or an oar or a boar...).
Handing the rock to his son, who turned it over in his hands like a rare treasure, the man and his children walked off again, sweeping the metal detector from side to side again.