Plummets have a distinctive “tear drop” shape, sometimes rounded, sometimes pointed at the bottom end. Plummets usually had either a ring cut around their circumference or a drilled hole for suspension.  They are usually manufactured from a dense, hard stone such as hematite or basalt.  

Numerous uses have been suggested, including that of a plumb bob for defining a vertical line in construction, a pendant used in personal adornment, a sinker for fishing lines or nets, a bola stone, or as a ceremonial or healing stone.

In the Lower Illinois Valley of west-central Illinois, plummets frequently have been found along the banks of backwater lakes and sloughs suggesting that they were used a weights for nets used in fishing or to capture migratory water fowl (ducks and geese).