Becquerelite

(repeating unit)Ca(UO₂)₆O₄(OH)₆·8(H₂O)IMA symbolBqr^[1]Strunz classification4.GB.10Crystal systemOrthorhombicCrystal classPyramidal (mm2)
H-M symbol: (mm2)Space groupPn2₁aUnit cella = 13.8378 Å,
b = 12.3781 Å,
c = 14.9238 Å; Z = 4IdentificationColourAmber-yellow, golden to lemon-yellow, yellow-orange, brownish yellowCrystal habitTabular prismatic striated crystals exhibiting pseudohexagonal outline; coatings and fine-grained aggregatesCleavagePerfect on {001}; imperfect on {101}, {010} and {110}TenacityBrittleMohs scale hardness2.5LustreAdamantine to greasyStreakYellowDiaphaneityTransparentSpecific gravity5.09–5.2Optical propertiesBiaxial (−)Refractive indexn_α = 1.725 – 1.735 n_β = 1.815 – 1.825 n_γ = 1.825 – 1.830Birefringenceδ = 0.100PleochroismX = colourless to pale yellow, Y = Z = yellow to deep yellow2V angleMeasured: 32°Common impuritiesCommonly contains leadOther characteristics RadioactiveReferences^[2][3][4]

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 by weight.

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

References