Celestite
 | This sample of celestite is on display at the Smithsonian Museum of Natural History. The size of the sample is about 10-12 cm high. Celestite is strontium sulfate, SrSO4.  |
 | This sample of celestite is is about 12x11 cm and is from Sakoany mine, Majunga, Madagascar. |
| Minerals |
| Selection of common minerals |
| HyperPhysics*****Geophysics | R Nave |