Finding sulfate contamination in crystallized silver nitrate What is the best way to check for a small amount of sulfate contamination (if any) in silver nitrate? Usually, I would use dilute barium chloride to precipitate out the resulting insoluble white barium sulfate in an unknown aqueous solution that contained sulfates. I tried this and got a white precipitate, but now I believe the precipitate I'm getting is insoluble silver chloride. 

Is there a better/different method to check for sulfates in silver nitrate? I was researching for a better solvent to use, but haven't been able to find any conclusive answers so far.
Barium nitrate has a water solubility of $\pu{10.5g/100mL}$ at $\pu{25^oC}$. It isn't specified in the question what concentration of sulfate you suspect might be present, but given that you are trying to check for sulfate by precipitating with barium, barium nitrate should be the way to go.