Well I've always been confused by platinum. They use it in catalytic converters, but it is almost as rare as gold, so it should have similar value one would think. As for solid gold, that would also be 24K gold. Gold however in lower grades such as 18K is often mixed with platinum. Gold is also sometimes mixed with pallidium to make white gold, but you never hear of a club called Pallidium. As for Pure Platinum/Solid Gold, they are numbers 78 and 79 on the periodic table of the elements, so they do occur right next to each other (right between Iridium and Mercury). As for Brass, it is an alloy of Copper and Zinc, Bronze is an alloy of copper and Tin, but I've never heard of a Bronze club or a Copper club, or a Zinc or Tin club for that matter. Go figure. I also find the credit card alloys interesting. My brother once got an offer for a "Titanium Card". Supposedly a step up from the "Platinum Card" or the now lowly "Gold Card", but Titanium is actually so abundant we use it as a pigment (in the form of Titanium Oxide) for making paint white. Somebody missed on that market study.