 Relative to most other elements , commercial applications for europium are few and rather specialized . Almost invariably , they exploit its phosphorescence , either in the + 2 or + 3 oxidation state . 
 Relative to most other elements , commercial applications for europium <a href='drop_aux' title='1'><mark>are</mark></a>few and rather specialized . Almost invariably , they exploit its phosphorescence , either in the + 2 or + 3 oxidation state . 
Relative to most other elements , commercial applications for europium few and rather specialized . Almost invariably , they exploit its phosphorescence , either in da + 2 or + 3 oxidation state .