Trap Rock Supplier | RaleighDurham, NC | Butner Trap Rock ...
Basalt is dark, dense, finegrained igneous rock formed from solidified lava in the earth''s crust. Hardness durability. Trap rock is among the hardest forms of rock in the In fact, according to Moh''s scale, which measures the hardness of aggregates, trap rock is ranked 8 – 9 and categorized as "critically hard."