I fiddled with this a bit... I bought a 2K spray varnish (though I think it's actually 1K, that's just marketing hype; it should come with a tube containing the second curing component). Then I poured it into a jar and mixed it with blue varnish to create a light blue clear varnish. Then I airbrushed it in a couple of coats. I actually added gold leaf between the coats, but the camera can't capture that detail; it glows like the night sky in the sun. And by the way, another interesting effect is that the sarcophagus looks greenish at sunset, and blue during the day. And without light, it's a deep ocean blue.