20139 - Beautiful Purple Natural Amethyst Crystals Cluster Minas Gerais District - Brazil Cobaltoan calcite The matrix has some fractures

The matrix has some fractures that have been glued together

This type of turtle remains in the Cretaceous are very rare

Iberocoryphe

The rear edges of the trailing side can create a 'roll-over' rim or 'lip' where the ablating/melting material has started to roll-over onto the back side

Kyrgyzstan

20139 - Beautiful Purple Natural Amethyst Crystals Cluster Minas Gerais District - Brazil Cobaltoan calcite The matrix has some fracturesAmethyst 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.