Samiresite

Where it forms, where it's found

2recorded occurrences

Source · OpenStreetMap

Radioactivity

Chemical composition

Constituent elements: Mass composition breakdown
Element Atoms At. mass g/mol Mass g/mol Mass share
92UUranium Uranium 2 238.029 476.058
24.66%
82PbLead Lead 2 207.200 414.400
21.47%
73TaTantalum Tantalum 2 180.948 361.896
18.75%
58CeCerium Cerium 2 140.116 280.232
14.52%
41NbNiobium Niobium 2 92.906 185.812
9.62%
8OOxygen Oxygen 7 15.999 111.993
5.80%
20CaCalcium Calcium 2 40.078 80.156
4.15%
9FFluorine Fluorine 1 18.998 18.998
0.98%
1HHydrogen Hydrogen 1 1.008 1.008
0.05%
Total 1930.553 100.00%
Mass share = atoms × atomic mass ÷ molar mass × 100
From Mindat formula

Mass composition breakdown
Element	Atoms	At. mass g/mol	Mass g/mol	Mass share
92UUranium	Uranium	2	238.029	476.058	24.66%
82PbLead	Lead	2	207.200	414.400	21.47%
73TaTantalum	Tantalum	2	180.948	361.896	18.75%
58CeCerium	Cerium	2	140.116	280.232	14.52%
41NbNiobium	Niobium	2	92.906	185.812	9.62%
8OOxygen	Oxygen	7	15.999	111.993	5.80%
20CaCalcium	Calcium	2	40.078	80.156	4.15%
9FFluorine	Fluorine	1	18.998	18.998	0.98%
1HHydrogen	Hydrogen	1	1.008	1.008	0.05%
	Total	1930.553	100.00%

Synonyms

Samiresit
Samiresita

Literature, links & citation

Citations

1912Lacroix, Alfred (1912) Sur un groupe de niobotantalates cubiques radioactifs des pegmatites du Vakinankaratra. Bulletin de Minéralogie, 35 (2) 84-92 doi:10.3406/bulmi.1912.3498DOI: 10.3406/bulmi.1912.3498
1922Lacroix, Alfred (1922) Minéralogie de Madagascar, Tome I. Géologie-Minéralogie descriptive. Augustin Challamel. 624 pp.
1977Hogarth, D. D. (1977) Classification and nomenclature of the pyrochlore group. American Mineralogist, 62 (5-6) 403-410
2010Atencio, D., Andrade, M. B., Christy, A. G., Giere, R., Kartashov, P. M. (2010) The pyrochlore supergroup of minerals: nomenclature. The Canadian Mineralogist, 48 (3) 673-698 doi:10.3749/canmin.48.3.673 DOI: 10.3749/canmin.48.3.673
2023Larsen, Knut Edvard (2023) Minerals first described from Madagascar. Norsk Mineralsymposium 2023, 89-122

Cite this entry

@misc{mineral2026,
  author    = {Mineral Index editorial board},
  title     = {Samiresite — Mineral Index},
  year      = {2026},
  url       = {https://mineralindex.org/minerals/samiresite-3514},
  note      = {Accessed 2026-05-11}
}