On melamine or formica I would use plumbers putty because if you have
to remove the sink you won't be as inclined to peel the laminate, On
stone or solid surface material silicone is an option because those
substrates ar far stronger.
YMMV

On Feb 3, 3:08 pm, "PVR" wrote:
I am dropping a new ceramic/vitreous sink into a melamine board counter top.
Things don't stick well to melamine surfaces.

What should I use as sealant between the rim of the sink and the melamine
surface?

Many thanks.

Peter.