Silver (Ag)

Atomic number: 47
Atomic weight: 107.868
Average concentration in ocean: 18 pmol/kg
Residence time: 350 years

Distribution in ocean
Silver has a modified, nutrient-like vertical profile.  The concentrations are low at the surface and increase continuously with depth (data).  Flegal et al. (1995) report a strong  correlation with Si.  

Speciation
Silver exists in seawater as the Ag+  ion in a complex with chloride AgCl2-. 

Residence time
The silver residence time is from Tracers in the Sea (Broecker, W. S. and Peng, T.-H., 1982.  Eldigo Press, Palisades, NY).  It was calculated from the global average river input.

Analysis
Silver is determined by an organic preconcentration and extraction followed by graphite furnace atomic absorption spectrophotometry.

References