Fixing the basin to the vanity

Ok, we are in the final straight. We took out the old vanity top and replaced with varnished wood. The new basin is meant to be stone but have since discovered it's made from that same stuff that the old top was made from. I had to file out the drain so it would take a 32mm waste and the plasticy smell was terrible. Gag!

Anyhow, this one sits on top of the benchtop with only the waste going through to the drain. Basin is black and I have black polyfilla. Will the polyfilla hold it in place or do I need glue?

Haven't researched this particular need in the past, but at a guess I'd probably use black SikaPro for that. It stays marginally flexible, which should cope well with the different surface materials at differing temperatures.

Similar but different situation, I used SikaPro for securing granite coping pavers to a fibreglass pool shell. That was 10 years ago, still going ..

My first thoughts would be Sikaflex 11FC, but would confirm what the material the basin is.

It's a basin from some developer/builder my wife met somewhere along the way. He had one left over. No idea what it's actually made from. Supposedly its stone. I dont believe that for a second. It's just not heavy enough. I've used 11fc before and it's great.

Thanjs all.