Becquerelite

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Becquerelite
Becquerelite-Uranophane-Uraninite-201144.jpg
Spray of becquerelite crystals with uranophane needles from the old Shinkolobwe mine
General
Category Oxide mineral
Formula
(repeating unit)
Ca(UO2)6O4(OH)6·8(H2O)
Strunz classification 4.GB.10
Crystal system Orthorhombic
Crystal class Pyramidal (mm2)
H-M symbol: (mm2)
Space group Pn21a
Unit cell a = 13.8378 Å,
b = 12.3781 Å,
c = 14.9238 Å; Z = 4
Identification
Colour Amber-yellow, golden to lemon-yellow, yellow-orange, brownish yellow
Crystal habit Tabular prismatic striated crystals exhibiting pseudohexagonal outline; coatings and fine-grained aggregates
Cleavage Perfect on {001}; imperfect on {101}, {010} and {110}
Tenacity Brittle
Mohs scale hardness 2.5
Lustre Adamantine to greasy
Streak Yellow
Diaphaneity Transparent
Specific gravity 5.09 - 5.2
Optical properties Biaxial (-)
Refractive index nα = 1.725 - 1.735 nβ = 1.815 - 1.825 nγ = 1.825 - 1.830
Birefringence δ = 0.100
Pleochroism X = colourless to pale yellow, Y = Z = yellow to deep yellow
2V angle Measured: 32°
Common impurities Commonly contains lead
Other characteristics Radioactive
References [1][2][3]

Becquerelite is a uranium mineral with the chemical formula: Ca(UO2)6O4(OH)6·8(H2O). It is a secondary mineral which contains calcium and is a bright yellow colour. It has a Mohs hardness of about 2.

It was named after the French physicist Antoine Henri Becquerel (1852–1908), who discovered radioactivity in 1896. Becquerelite contains about 70% Uranium in it.

It is mainly mined in Kasolo of the former Zaire, in the present day Democratic Republic of the Congo.

References[edit]