I went to seal a white cork decoy with some spar varnish to find it had hardened in the can. I have a jar of traditions cork sealer I will use. I have not used any of the traditions sealer yet. Is it as good as spar varnish or should I hold out until I can get a new can of varnish? I need varnish for the wood head anyway. Just getting impatient this evening to make progress.