Optimal
Reinforced concrete, Concrete, Brick, Roof tile, Cured concrete hard, Cured concrete medium, Cured concrete soft
Good
Concrete hard, Concrete medium, Concrete soft, Flint concrete hard, Granite, Marble, Natural stone, Abrasive, Iron, Ductile iron
Acceptable
Block, Ceramic tiles, Green concrete (abrasive) hard, Green concrete (abrasive) soft, Asphalt