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| Forsterite (fo90 fa10) pebbles show the typical green 'peridot' color |
Class
presentation on cation occupancy (PowerPoint
presentation - 1.6 MB)
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| Forsterite (fo90 fa10) pebbles show the typical green 'peridot' color |
Does site occupancy make any difference?
Above are synthetic Ni-containing olivines. The green color if from a sample with most of the nickel in the M1 site. The yellow crystal is LiScSiO4 with added nickel; in this crystal the nickel is forced to go into the M2 site.
The color difference is directly due to the different site occupancies.
Olivine from the upper mantle transported in a basalt flow near
San Carlos, Arizona. The darker grains admixed with the
olivine are pyroxene.