AG Hair Sterling Silver Toning Shampoo 
Shampoo Sterling Silver is specifically formulated to eliminate brassy, yellow tones from blonde and silver hair.  With its unique violet base, this mild toning shampoo removes dullness and brassiness, leaving blonde and silver hair looking cleaner and brighter.  pH 4.5-5.5. 
Directions:  Massage into wet hair.  Rinse and repeat as desired.  Use once or twice a week for color maintenance or more frequently for persistent discoloration.