I did find about four pre 1920 silver coins in the years 1975-79 if I remember rightly they were sixpences and shillings no florins so it was prob only 10p face value - they were in dire straits and it was very hard to work out what the dates were , they were true "scrap only" coins .
TBH it was hardly even worth looking with the amount you found , I remember the best place to be given silver was by passing a note to an ice cream van , it's logical if you think about it , pester power would get parents to seach the bottom of a drawer to find a coin for little billys ice cream