Natural Bastnasites Overview
 Bastnasite was named in 1841 after its descovery locality, at Bastnas, Sweden. Sometimes Bastnasite is also spelled as Bastnaesite. This stone is of a few rare earth carbonate minerals.
Bastnasite forms a series with the mineral hydroxylbasnasite. The two are members of a substitution series that involves the possible substitution of fluorine ions for hydroxyl (OH) ion groups. Hydroxylbasnasite has a formula of (Ce, La)CO3(OH, F). Not an obviously significant difference, but significant enough to warrant a new mineral. X-ray studies confirm that the hydroxyl ion groups increase the unit cells of the structure and crystallographically and mineralogically this is significant.
The structure of bastnasite is made up of stacks of carbonate ion layers and CeF layers. The CeF layers form flat hexagonal sheets with each cerium bonded to three fluorines. The carbonate layers are more complex with angled carbonate triangular groups. The structure is closely studied because it is one of the few rare earth mineral structures that can accommodate variously sized cations.
Physical Properties
| Color |
white, gray, yellow, pink, brown |
| Pleochroism |
Faint |
| Chemistry |
Ce(CO3)F |
| Hardness |
4.3 |
| Density |
4.97 |
| Crystal Group |
Hexagonal |
| Ocurrence |
Sweden, Norway, Malawi, Turkey, Hungary, Greece, Pakistan |
Legend and Lore
Browse Bastnasites
The pictures above only represents the general appearance of the Bastnasite. Please note that the real Bastnasites in our stock will be of varied shapes, color and sizes.
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