The parallel lines on the bearing seams to indicate there's a problem with the finishing on the crank, dirt aside. The first pic has lost most of the the top coat of babbit, the second bearing is dirt or metal. The main and first rod pic says crank finish. Polish the bearing with anything and they are no longer tri-metal, but now bi-metal bearings. The babbit is soft, thin, and porous, and designed to capture and hold micro particles of carbon to protect the crank surface. You no longer have that protection.