Boulders: large to very large stones that may be rounded or angular, and of limestone, sandstone or granite
Slabs: or what are sometimes referred to as outcroppings, are large flattish pieces of natural stone
Coverage Calculation:
Single Round Boulders: in feet, calculate the area of a sphere of the approximate diameter of a desired boulder (A = 4/3 x Pi x radius cubed). Note: An ellipsoid of the same diameter and twice the length of a sphere, equal two times the volume of the sphere.
Angular Boulders: use the slab method below
Single Slab: in feet, calculate the average thickness x average length x average width = cubic feet
Wall: in feet, calculate the average height x average depth x average length = cubic feet
Cubic Feet Weight:
Limestone = 165 pounds
Sandstone = 150 pounds
Granite = 175 pounds