Fermiite, Na (sub 4) (UO (sub 2) )(SO (sub 4) ) (sub 3) .3H (sub 2) O and oppenheimerite, Na (sub 2) (UO (sub 2) )(SO (sub 4) ) (sub 2) .3H (sub 2) O, two new uranyl sulfate minerals from the Blue Lizard Mine, San Juan County, Utah, USA

The new minerals fermiite (IMA2014-068), Na (sub 4) (UO (sub 2) )(SO (sub 4) ) (sub 3) .3H (sub 2) O and oppenheimerite (IMA2014-073), Na (sub 2) (UO (sub 2) )(SO (sub 4) ) (sub 2) .3H (sub 2) O, were found in the Blue Lizard mine, San Juan County, Utah, USA, where they occur together as secondary alteration phases in association with blodite, bluelizardite, chalcanthite, epsomite, gypsum, hexahydrite, krohnkite, manganoblodite, sideronatrite, tamarugite and wetherillite. Fermiite descriptive details: pale greenish-yellow prisms; transparent; vitreous lustre; bright greenish-white fluorescence; white streak; hardness (Mohs) 21/2; brittle; conchoidal fracture; no cleavage; slightly deliquescent; easily soluble in RT H (sub 2) O; densitymeas=3.23(2) g cm (super -3) ; densitycalc=3.313 g cm (super -3) . Optically, biaxial (+), alpha =1.527(1), beta =1.534(1), gamma =1.567(1) (white light); 2V (sub meas.) =51(1) degrees , 2V (sub calc.) =50 degrees ; dispersion r<v, distinct. Pleochroism: X, Y=colourless, Z=pale greenish yellow; X=Y<Z. Energy dispersive spectroscopic (EDS) analyses yielded the empirical formula Na (sub 3.88) (U (sub 1.05) O (sub 2) )(S (sub 0.99) O (sub 4) ) (sub 3) (H (sub 2) O) (sub 3) . Fermiite is orthorhombic, Pmn2 (sub 1) , a=11.8407(12), b=7.8695(5), c=15.3255(19) Aa, V=1428.0(2) Aa (super 3) and Z=4. The structure (R (sub 1) =2.21% for 1951 I (sub o) >3sigma I) contains [(UO (sub 2) )(SO (sub 4) ) (sub 3) ] chains that are linked by bonds involving five different Na-O polyhedra to form a framework. The mineral is named for Italian-American theoretical and experimental physicist Dr. Enrico Fermi (1901-1954). Oppenheimerite descriptive details: pale greenish-yellow prisms; transparent; vitreous lustre; bright greenish-white fluorescence; white streak; hardness (Mohs) 21/2; slightly sectile; three good cleavages, {110}, {011} and {101}; irregular fracture; slightly deliquescent; easily soluble in RT H (sub 2) O; densitycalc=3.360 g cm (super -3) . Optically, biaxial (+), alpha =1.537(1), beta =1.555(1), gamma =1.594(1) (white light); 2V (sub meas.) =72(2) degrees , 2V (sub calc.) =70 degrees ; dispersion is r>v, moderate, inclined; optical orientation: X congruent to perpendicular to {101}, Z congruent to [111]; pleochroism: X very pale greenish yellow, Y pale greenish yellow, Z greenish yellow; X<Y<Z. EDS analyses yielded the empirical formula Na (sub 1.94) (U (sub 0.97) O (sub 2) )(S (sub 1.02) O (sub 4) ) (sub 2) (H (sub 2) O) (sub 3) . Oppenheimerite is triclinic, P1, a=7.9576(6), b=8.1952(6), c=9.8051(7) Aa, alpha =65.967(5), beta =70.281(5), gamma =84.516(6) degrees , V=549.10(8) Aa3 and Z=2. The structure (R (sub 1) =3.07% for 2337 I (sub o) >3sigma I) contains [(UO (sub 2) )(SO (sub 4) ) (sub 2) (H (sub 2) O)] chains that are linked by bonds involving two different Na-O polyhedra to form a framework. The mineral is named for American theoretical physicist Dr. J. Robert Oppenheimer (1904-1967).