21570 - Association Quartz + Pyrite + Barite Crystals - Alnif (Morocco) Gypsum Tooth 2: 80 mm (3

Tooth 2: 80 mm (3

Amygdules are scarce in the sample and are filled by calcite

Phalangocephalus

akaganeite (Fig

Beautiful example of 17

21570 - Association Quartz + Pyrite + Barite Crystals - Alnif (Morocco) Gypsum Tooth 2: 80 mm (3Quartz is a mineral composed of silicon and oxygen atoms in a continuous framework of SiO4 siliconoxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO2. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. The mineral pyrite, or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula FeS2 (iron(II) disulfide). Pyrite is