I bought a commercial lathe yesterday. One piece alone weighs nearly a ton. It came with many different pieces. All of it is iron, but some pieces of the same size are much heavier than others. Any easy way of telling the difference between regular cast iron and heavy iron, other than by weight?
My yard is paying $260 for steel, $280 for iron, and I think $310 for heavy, so this knowledge would be pretty 'valuable'.