Does anyone know of a matte glass sealer that wont wash off?

I'm working on a mosaic piece with stained glass and the client is concerned about glare. I need to reduce the glare any suggestions.


ThanksDoes anyone know of a matte glass sealer that wont wash off?
Weird. Use stone. Sandblast the glass after setting. Fuse glass and cool slowly to devitrify surface. Satin finish polyeurethane varnish. What did the client think they were getting, dull art?

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