Palladium, a soft shiny silvery-white metal, is one of six platinum group metals and is relatively rare. It was discovered in 1803 by William Hyde Wollaston. Palladium often replaces platinum since it is cheaper, harder and lighter. It can be drawn into wire or hammered out into sheets, it is often mixed with gold for “white gold” jewelry. Palladium can also be used to make surgical instruments. Automobile manufacturers need the world’s palladium for catalytic converters. Along with gold, silver, and platinum, palladium is a precious metal owned and traded by investors.
Which is a valid comparison supported by this passage?
