plaster on shower tray

kev1744

hi all,
hope someone can help. im in process of refurbishing the bathroom.the plasterers for some reason didnt bother to cover the stone shower tray when they plastered ...now its covered in plaster which im struggling to get off cleanly.
anyone have any ideas on how to get the tray clean again?

tia  

stuart45

Block the drain and keep it soaked. Water softens up plaster. Best not to scrape it off and scratch the tray. 
Have you paid them yet?

kev1744

unfortunately they have been paid. i was away for a few days whilst they did work so only found out when i got back. im less than happy as i would have thought putting a sheet of plastic down would have been normal practice.