Weatherproof Glass Paint for COE 47?

I'm looking for a glass paint/enamel/vitreous enamel to use on glass block (Pittsburgh Corning COE 47).

It needs to be weatherproof as it will be outdoors 100% of the time, albeit in Southern California "weather", if you can call it that. Needs to be transparent too.

Need to stay under 1300F, blocks start ballooning then.

Are Fuse Master Transparent Enamels appropriate for this? Are there better choices? And, is there a gold luster that would hold up in the weather?

Thanks very much,

Steve J. Noll | Ventura California | Glass Block Pond