EKANITE: Sri Lanka (~ 0.5)
Ekanite is metamict as a result of the U and Th content. The properties vary, depending on the degree of breakdown of the structure. Ekanite is one of the very rarest of all gems, and only a few are known. More undoubtedly exist that have been sold as other Sri Lankan gems, but the total number of gems is a mere handful.
Ekanite Value
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Ekanite Information
| Data | Value |
| Name | Ekanite |
| Crystallography | Tetragonal. Crystals elongated parallel to long crystal axis; massive pebbles. |
| Colors | Green, dark brown, light brown, emerald green. |
| Luster | Vitreous |
| Hardness | 5-6.5 |
| Density | 3.28-3.32 |
| Birefringence | 0.001 |
| Cleavage | None |
| Stone Sizes | A stone was tested by the London Gem Labs in 1975: 43.8 carats, blackish color, S.G. = 3.288, R.I. = 1.595 (average); radioactive; 2 spectral lines seen. A 351 carat rough has also been reported. |
| Luminescence | Not diagnostic. |
| Spectral | May show lines at 6300 and 6580. |
| Formula | (Th,U)(Ca,Fe,Pb)2Si8O20. |
Optics: o = 1.573; e = 1.572.
Uniaxial ( – ). Gems usually 1.590-1.596.
Occurrence: Discovered in 1953 as waterworn, translucent green pebbles at Eheliyagoda, near Ratnapura, Sri Lanka. Occurs in the gem gravels. Some cut Sri Lankan stones have 4-rayed stars. Mt. Ste. Hilaire. Quebec, Canada.
Central Asia.
Comments: Ekanite is metamict as a result of the U and Th content. The properties vary, depending on the degree of breakdown of the structure. Ekanite is one of the very rarest of all gems, and only a few are known. More undoubtedly exist that have been sold as other Sri Lankan gems, but the total number of gems is a mere handful.
Name: After E L. D. Ekanayake who first found it in a Sri Lankan gravel pit.
