Rutherfordine

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Rutherfordine
A conglommeration of glassy, yellowish crystals
Rutherfordine (light yellow, top) together with billietite
General
Category Carbonate mineral
Formula
(repeating unit)
UO2CO3
Strunz classification 05.EB.05
Crystal symmetry Orthorhombic pyramidal H–M Symbol mm2
Unit cell a = 4.840 Å, b = 9.273 Å, c = 4.298 Å; Z = 2
Identification
Colour Brownish, brownish yellow, white, light brown orange, or light yellow
Crystal habit Crystals are Lathlike, elongated crystals commonly radiating, fibrous, matted; earthy to very fine-grained masses.
Crystal system Orthorhombic
Cleavage perfect on {010}, good on {001}
Luster Silky, dull
Streak Yellow
Diaphaneity Transparent
Specific gravity 5.7
Optical properties Biaxial (+)
Refractive index nα = 1.700 - 1.723 nβ = 1.716 - 1.730 nγ = 1.755 - 1.795
Birefringence δ = 0.055 - 0.072
Pleochroism Visible X= colorless, Y= pale yellow, Z= pale greenish yellow
2V angle Calculated: 53°
Other characteristics Radioactive
References [1][2][3]

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.[2]

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.[1] It forms under acidic to neutral pH and is the only known mineral that contains only uranyl and carbonate.

References[edit]

  • Palache, C., H. Berman, and C. Frondel (1951) Dana’s system of mineralogy, 7th ed., v. II, pp. 274–275.