Rutherfordine

Rutherfordine
A conglommeration of glassy, yellowish crystals
General
CategoryCarbonate mineral
Formula
(repeating unit)		UO2CO3
IMA symbolRfd[1]
Strunz classification5.EB.05
Crystal systemOrthorhombic
Crystal classPyramidal (mm2)
H–M Symbol: (mm2)
Space groupImm2
Unit cella = 4.840 Å, b = 9.273 Å
c = 4.298 Å; Z = 2
Identification
ColourBrownish, brownish yellow, white, light brown orange, or light yellow
Crystal habitCrystals are Lathlike, elongated crystals commonly radiating, fibrous, matted; earthy to very fine-grained masses.
Cleavageperfect on {010}, good on {001}
LustreSilky, dull
StreakYellow
DiaphaneityTransparent
Specific gravity5.7
Optical propertiesBiaxial (+)
Refractive indexnα = 1.700 - 1.723 nβ = 1.716 - 1.730 nγ = 1.755 - 1.795
Birefringenceδ = 0.055 - 0.072
PleochroismVisible X= colorless, Y= pale yellow, Z= pale greenish yellow
2V angleCalculated: 53°
Other characteristics Radioactive
References[2][3][4]

Rutherfordine is a mineral containing almost pure uranyl carbonate (UO2CO3). It crystallizes in the orthorhombic system in translucent lathlike, elongated, commonly radiating in fibrous, and in pulverulent, earthy to very fine-grained dense masses. It has a specific gravity of 5.7 and exhibits two directions of cleavage. It appears as brownish, brownish yellow, white, light brown orange, or light yellow fluorescent encrustations. It is also known as diderichite.

It was first described in 1906 for an occurrence in the Morogoro Region of Tanzania. It was named for Ernest Rutherford. It has been reported in the Democratic Republic of Congo, the Northern Territory of Australia and a variety of locations worldwide.[3]

It occurs as a secondary mineral as a weathering product of uraninite. In addition to uraninite it occurs associated with the rare minerals becquerelite, masuyite, schoepite, kasolite, curite, boltwoodite, vandendriesscheite, billietite, metatorbernite, fourmarierite, studtite and sklodowskite.[2] It forms under acidic to neutral pH and is the only known mineral that contains only uranyl and carbonate.

References

  1. ^ 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.
  2. ^ a b Handbook of Mineralogy
  3. ^ a b Mindat with location data
  4. ^ Webmineral data
  • Palache, C., H. Berman, and C. Frondel (1951) Dana's system of mineralogy, 7th ed., v. II, pp. 274–275.