09157 - Huge Brown Natural Amethyst Geode Minas Gerais District - Brazil Prionolepis cataphractus This enormous Prognathodon tooth is

This enormous Prognathodon tooth is preserved associated with Squalicorax shark tooth

Morocco Date: P 2018 Mass (g): 7

It has tiny glued or filled fractures

Ginglymostoma ypresiensis

Mass: 1 t Classification

09157 - Huge Brown Natural Amethyst Geode Minas Gerais District - Brazil Prionolepis cataphractus This enormous Prognathodon tooth isAmethyst is a purple variety of quartz (SiO2) and owes its violet color to irradiation, impurities of iron and in some cases other transition metals, and the presence of other trace elements, which result in complex crystal lattice substitutions. The hardness of the mineral is the same as quartz, thus making it suitable for use in jewelry.