A cubic yard of gravel weighs between 2,200 and 2,600 pounds, depending on the type of gravel selected. Washed gravel and limestone base tend to be heavier, while landscape gravel and washed limestone are the lightest.
In most cases, a cubic yard of gravel provides enough material to cover a 100-square-foot area with 3 inches of gravel. Some material compacts more than others, so the exact coverage is sometimes less.
In some applications, lava rock is an acceptable substitute for gravel. This porous material is lighter than normal gravel, weighing between 1,000 and 1,300 pounds per cubic yard. Lava rock is easier to haul and less work to spread than ordinary gravel.
Volume is a measure of how much space an object or a quantity of a substance fills, while weight is a measure of the gravitational force the earth exerts upon an object. Volume is calculated by dividing the mass of an object by its density. The non-metric system of measurement customarily used in the United States lacks a unit for mass, which refers to the amount of matter an object contains and is not relative to gravity. Thus, calculating the weight in pounds of 1 cubic yard of a dry material, such as gravel, may first require conversion of cubic yards to grams, a metric measurement of mass, before arriving at an estimated weight equivalent in pounds.