Mineral Species: Quartz var. Chalcedony

Chemical Formula: SiO2

Chemical Name: Silicon Dioxide

Mineral Class: Tectosilicate

Mineral Notes: Chalcedony is a microcrystalline variety of quartz, frequently occurring as botryoidal masses. It forms by the slow precipitation of silica from aqueous solution and is found in a huge variety of shapes and forms.

Description: A very pleasing  specimen of Chalcedony. The outside is irregular and has an attractive creamy-pink colour. The interior consists of spherical aggregates and individual crystals of Quartz. These are white and very lustrous.

Location: N'Chawaning Mine, Cape Province, South Africa.