Bismuth is a brittle metal with a white, silver-pink hue, often occurring in its native form with an iridescent oxide tarnish showing many colors from yellow to blue. The spiral stair stepped structure of a bismuth crystal is the result of a higher growth rate around the outside edges than on the inside edges.
Bismuth crystals | If you want one of the rarest bismuth crystals in the world, here it is!!! It was amazing seeing this creation come forth from the molten bismuth. Simply massive in size at 566 grams, and 4 1/2” by 4 1/8” by 3”. It has gorgeous pastel colors of greens, pinks, oranges, yellows, purples, blues, browns and golds.
Osmium is both the densest and the rarest element that you can dig out of the Earth. It's so hard that it's used (as an alloy) in places with constant pressure and wear, like the tips of fountain pens. One single cubic inch of this stuff weighs nearly a pound, and were you to somehow get a cubic foot of it, it would weigh over 1,400 pounds. Good luck with that, though: last year, the entire U.S. osmium production was only 165 pounds.