Hey Linda........Henry is right - as are all the others here who think painting counter tops is a terrible idea.
Search "painting counter tops" sometime - see what you find. They just aren't made to be painted.
As for crackle - it is a hydrophylic product - that means it "loves water"...water is what makes it work - it sucks the water out of the topcoat so quickly that the topcoat cracks.
Does this sound like something you want on a bathroom vanity? I don't think so. Your oil based sealer would have to be great to keep the water from getting to the counter and making it crack more.
Do yourself a favor - save up your $$ - and buy new vanity tops - you may even be able to find ones that look crackled!
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