Allow the polyurethane to dry two to three hours.
Polyurethane on marble table.
I would use a product called soy gel.
I purchase a marble topped coffee table for 5 because someone put polyurethane over the marble so it wouldn t chip.
Use a sealer made to seal marble.
The marble is less likely to scratch as is why it is used as a cutting board surface.
The foam forms bubbles on the surface and if they harden they can be difficult to camouflage.
Polyurethane tends to gum up sandpaper so use paper or pads that resists clogging 320 grit.
Apply a second coat if you desire.
I want to remove it but not sure how.
I also told you the only viable fix for your problem.
Clean off the white stuff.
A quick hand sanding between coats flattens our flaws before the next coat.
Poly will scratch and flake off looking worse than a few scratches in the stone.
So in my opinion i would not use polyurethane on your marble top.
Dip your brush gently and take your time painting the surface.
Watch as rachelle from originally worn attempts and slightly fails to finish a table top with annie sloan graphite unicorn spit polyurethane.
Polyurethane products especially water based ones tend to foam when you agitate them.
Let the polyurethane sit for about 10 minutes after stirring to allow the foam to settle.
Your question was can i put polyurethane on marble i answered this question.
Best to stay away from poly for this purpose.
You can get from here.
Turn an old table into a marble master piece with just some simple steps some paint and sticky back vinyl.
A sealer would be good to stop staining however bleach or a marble cleaner can be used to remove stains.
Although it is possible that your table has a polyurethane or varnish finish it s much more likely that the marble was polished to a high gloss that has become scratched and dull.
On shaped edges use synthetic steel wool such as scotch brite pads labeled very fine tabletop finishing.
It will penetrate the surface and protect it.
The shine most likely will not last and and when it begins to break down it will look very bad.
The table is going to be my new desk but at the m.