Notat Home wrote:
We have a cultured marble sink with a couple of hairline cracks
radiating out from the outlet, less than half an inch in length.

There is no leakage, and the cracks don't appear on the bottom of the
sink, so I think this is just a cosmetic problem, but I would like to
fix it.

I've read that polymer resin can be used for this purpose, but I think
these cracks, being hairline width, are too tight for resin to get
into the cracks, which makes me think I should widen the cracks before
applying the resin, which I'm not real eager to do lest I make a small
problem into a big one.

Is there a very thin, watery resin that would sink into a hairline
crack, or a proven technique to solve this problem, or should I just
keep ignoring it?

you can get a water thin epoxy, used for this application. try a place that
sells granite slabs. i've used http://www.defusco.com/ for granite tools
and such. good prices and excellant service (no affiliation, yada).