*3.3.1 Olivines*

In the caldera of the Mount Bambouto, olivine is present in the basalts with an average size of 0.5 × 3 mm. It is automorphic to subautomorphic. Their section is traversed by numerous cracks along which one notes the beginning of iddingsitization and serpentinization. Some sections have a core and borders corroded by mesostase. The olivine in the caldera of the Mount Bambouto is globally magnesian with forsterite contents between Fo57 and Fo75 (**Figure 6**).
