Synthetic Fluorescent Mineral experiment: colors of Uranium - UVc

FOV: 2.5" wide.

 

The vast majority of minerals containing the uranyl ion (UO2)+2 fluoresce a yellowish green. A small group of minerals have this green fluorescence shifted toward the blue. These minerals include liebigite: Ca[UO2(CO3)3] * 10-11H2O, andersonite: Na2Ca[UO2(CO3)3] * 6H2O and shrockingerite: Na2Ca3[UO2(CO3)3](SO4)F * 10H2O.

 

A common anion in these three minerals is the carbonate ion. I wondered if this might be the cause of the blueward shift in the spectrum.

 

See: rruff.info/uploads/CM31_167.pdf

 

 

Equal amounts (by volume) of calcium chloride, sodium carbonate and uranyl nitrate were combined with water. The resulting precipitate (calcium carbonate) was filtered and the remaining solution was left to recrystallize. The precipitate showed no fluorescence

 

The recrystallized solution produced minerals with two distinct colors of green luminescence, yellow-green and blue-green. My current hypothesis is that the blue-green material may be andersonite. The main component of the material should be NaCl.

 

Contains:

?? (uranyl) (FL Yellow green >UVbc)

?? (uranyl) (FL Blue green >UVabc)

 

Shown under UVc light.

 

Key:

WL = White light (halogen + LED)

FL = Fluoresces

PHOS = Phosphorescent

Blue = 455nm,

UVa = 368nm (LW), UVb = 311nm (MW), UVc = 254nm (SW)

'>' = "stimulated by:", '!' = "bright", '~' = "dim"

 

Obtained from the "lab" in my basement. 18Jun2015

 

Thanks to Gordon Czop for the uranyl nitrate.

 

18 Watt Triple Output UV lamp from Polman Minerals - Way Too Cool UV lamps

Done