Slickenside

Harness is an old miner term for a movement track on a fault plane, which is caused by the fact that another rock sliding packages have smoothed the surface. This leave harder rocks embedded components on the sliding surface scratches in the direction of the displacement. They are an indication of movements and their direction in the geological past. The parallel striations often have fine separation edges. Based on these edges can the relative motion of the rock pacts reconstruct each other.

In cases where the sliding surface was polished in the movement, one also speaks of a mirror armor.