7.—Asphaltum.
Occurs massive; brittle; breaking with high lustre like hardened tar, and with curved surface; melts and burns readily with flame and smoke; gravity 1.2, sometimes floats on water.
Value.—Used for cements and varnishes.
Localities.—Found generally near the surface. Near the coast of Santa Barbara, Cal.; West Virginia, twenty miles south of Parkersburg.