Working with sea glass

Please can someone explain the green sea glass topic arose a while
ago i do a lot of wandering on our beaches and know there have been
quite a few ship wrecks i find some very dark green thick
glassbroken bottles the bases are very irregular no trade marks very
roughly made found some in a mass of agglomerated shells and stone
with gun shot and base of rifle brass etc apparently bottles used for
whale sperm oil is this the sea glass you are talking about how do i
polish and work them i do have a lot of diamond abrasives 250 to 2500
grade in belts and rolls and discs like used for granite polishing
and marble. who knows

thanks frank