bijvoetite-(Y)

{{infobox mineral | name = Bijvoetite-(Y) | category = Carbonate mineral | image = | imagesize = | alt = | caption = | formula = (Y,REE)8(UO2)16(CO3)16O8(OH)8•39H2O | IMAsymbol=Bij-Y | molweight = | strunz = 5.EB.20 (10 ed) 5/F.06-30 (8 ed) | dana = 16b.2.4.1 | system = Monoclinic | class = Spheroidal (2) (same H-M symbol) | symmetry = B21 | unit cell = a = 21.23, b = 12.96, c = 44.91 [Å], β = 90.00° (approximated); Z = 4 | color = Yellow | colour = | habit = Plates | twinning = | cleavage = {001}, good | fracture = | tenacity = | mohs = 2 | luster = Vitreous | streak = Light yellow | diaphaneity = Transparent to translucent | gravity = | density = 3.97 (measured) | polish = | opticalprop = Biaxal (+) | refractive = nα = 1.60, nβ = 1.65, nγ = 1.72 (approximated) | birefringence = | pleochroism = Colorless (X), pale yellow (Y), deep yellow (Z) | 2V = 84° (measured) | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = 25px Radioactive | references = }} Bijvoetite-(Y) is a very rare rare-earth and uranium mineral with the formula (Y,REE)8(UO2)16(CO3)16O8(OH)8·39H2O. When compared to the original description, the formula of bijvoetite-(Y) was changed in the course of crystal structure redefinition. Bijvoetite-(Y) is an example of natural salts containing both uranium and yttrium, the other examples being kamotoite-(Y) and sejkoraite-(Y). Bijvoetite-(Y) comes from Shinkolobwe deposit in Republic of Congo, which is famous for rare uranium minerals. The other interesting rare-earth-bearing uranium mineral, associated with bijvoetite-(Y), is lepersonnite-(Gd).

The mineral is named after the Dutch chemist and crystallographer Johannes Martin Bijvoet.