As a coloring agent, this element between iron & nickel on the periodic table will literally give you the blues
Periodic 
table .... An increase in the carbon content of the iron will initially cause a 
significant... [DOC] [TLE] Absorptiometric Methods in Rapid Silicate Analysis [PAR] chemical procedures will be more attrac- tive for those elements for which satis- 
... nickel crucible of the same size: If a ... unlike that of the silicomolybdenurn 
blues (2).