A contractor showed me how to fix dents in granite with superglue. It’s totally clear. The trick is to scrape it with a razor blade at a 90 degree angle (strait horizontal). The imperfections become nearly invisible.

This is also how glass chip repair works. If the polymer has a close enough index of refraction to the glass, it's invisible.

I've been told this is a cheap way to fix small windshield cracks. Never tried it but sounds like it would work for the small spider sized and shaped cracks from small rock impacts.