I doubt you will have success in bonding molten Au to glass with a surface
layer of Au in place. Do you have some kind of adhesion layer such as
Cr or Ti on the surface?

The only viable way to bond a layer of Au to glass is to use a gold-bright
solution (colloidal gold in oil of lavendar) or a glass frit/Au powder
combination. Fire these on and then electroplate. Englehard used to make
Pt and Au bright solutions which are routinely used in the ceramics industry
to decorate procelain.

                                        Bob Hamilton
                                        Formerly, Principal Glassblower, UC


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