| Lecontite | |
|---|---|
| General | |
| Category | Sulfate mineral |
| Formula (repeating unit) | (NH4,K)NaSO4·2H2O |
| IMA symbol | Lcn |
| Strunz classification | 7.CD.15 |
| Crystal system | Orthorhombic |
| Identification | |
| Color | Colorless |
| Cleavage | {011} Distinct |
| Mohs scale hardness | 2–2.5 |
| Luster | Vitreous to dull |
| Streak | White |
| Diaphaneity | Transparent to translucent |
| Specific gravity | 1.745 g/cc |
| Density | 1.745 g/cc |
| Refractive index | nα = 1.440 nβ = 1.454 nγ = 1.455 |
| Birefringence | δ = 0.015 |
Lecontite (sodium ammonium sulfate dihydrate, with potassium substituting for some ammonium, typically about a fourth) is a sulfate mineral with the formula (NH4,K)NaSO4·2H2O. It was found by John Lawrence LeConte in Las Piedras Cave in Honduras as a breakdown product of bat guano, including crystals up to an inch long and identified as a separate mineral by W.J. Taylor in 1858. As of 1963 most natural specimens came from the same cave.
Lecontite can easily be synthesized by reacting ammonium sulfate with sodium sulfate in aqueous solution and crystallized.
References
- Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
- ^ "Lecontite Mineral Data". Webmineral. Retrieved 2022-04-15.
- ^ "Lecontite". Mindat.
- Taylor, W.J. (1858). "Lecontite, a new mineral". American Journal of Science and Arts. 76: 273–274.
- Faust, Robert J.; Bloss, F. Donald (1963). "X-ray study of lecontite". American Mineralogist. 48 (January–February): 180–188.
- Shintyakov, Dmitry. "Sodium ammonium sulfate". DmiShin home, crystal growing collection. Retrieved 2022-04-15.
This article about a specific sulfate mineral is a stub. You can help Misplaced Pages by expanding it. |