Discovery from the Color of Minerals link

I'd never heard of the mineral Wulfenite (PbMoO4) before. It's colors are red, orange, yellow silver and white and it is found in Morocco, Nambia, Mexico and Arizona and New Mexico. Wulfenite almost always forms in thin tabular crystals. On the large thin plates the prism faces are often irregularly developed so that the crystals are not sharply bounded. What caught my attention is that they mentioned Wulfenite as being a symmetrical enigma. Apparently there are conflicting results in various symmetry tests which is extremely rare. It is either a symmetry of 4 or 4/m.