A chemist gave me enough potassium chromate to have a go. Ground off a few
mg from some sheet lead , dropped into some chromate solution and a cloudy
yellowish deposit formed in the otherwise orange liquid - what it is
supposed to do apparently.
Then ground off some known lead free solder , added to some of the solution
and no yellow.
Then ground off some known SnPb solder and again no yellow - so not so
simple a test as first appeared, Pb and tin are combined too well to react ?