The three men stood on the lakeshore. The water was still blue, but the rust and brown tundra foliage and the skiff of snow on the ground told them it would soon freeze over for the winter. They strode to the south shore and dug up rocks and gravel. Nothing. They quickly moved to the north shore. More digging and rock hammering. Still nothing. Then they moved toward the esker, a huge embankment of sand and gravel snaking across to the horizon. As they passed outcrops of bedrock, one of the men pointed out striations and glacial erratics that indicated ice had passed over this area tens of thousands of years ago. The ground was covered with mud boils heaved out of the ground by frost. Some were over a metre in diameter: big, round pustules with heads full of indicator minerals— just the kind of minerals that indicate the presence of diamonds.