This stone comes in random shapes and sizes, and is sometimes referred to as: flag, flagstone, builder, irregular builder, fieldstone, or mosaic.Size: Typically the face is larger than a dinner plate, but smaller than a chair cushion; 3-5 thickCoverage: 40-45 square feet per ton (approximate)When installed as natural patio stone: Size: Typically the face is larger than a dinner plate, but smaller than a chair cushion; 2-3 thick (approximate)Coverage: 75-80 square feet per ton (approximate)