Levels of Quality, Sizes, Edges, and Joining Systems. Shaw classifies its floors as Good, Better, Best, and Superior. Most floors fall in the Better or Best categories, with some floors falling into both categories at once (doubling the wear layer thickness bumps a product up to the Best level).
If your shelf projects 1 1/2 inches or less, there must be at least six inches between the top of the fireplace and the mantel. Any parts of the mantel that project more than 1 1/2 inches must be at least 12 inches from the top of the fireplace.
The Earth's mantle is a roughly 1,800 mile (2,900 km) thick shell of compressed and heated rock, beginning below the Earth's crust (lithosphere), which extends 3.1 miles (5 km) below the ocean floor and 19 to 31 miles (30 to 50 km) below the continents.