Aliminum marks on polished porcelain

[kaharrison9]

May be of intrest to anyone.
Noticed my spirit level was leaving dull silver marks on some ivory polished porcelain.
Tried rubbing off with rubber,cloth,scouring pad to no joy then tried the adhesive i was using with has very fine sand content.It took it immediatley off and no scratches

 

[DHTiling]

All tips appreciated..🙂

 

[TilerBhoy]

I have used Bar Keepers friend before, works a treat