prints - What method is used for printing onto museum-quality glass?

I'm looking for a service bureau that can print directly on museum quality glass. I am not sure what the method/process used for this is. Is this done with an inkjet printer? What color space is used? Is it RGB or CMYK? Is it printed on the surface of the glass or is it molecularly bonded similarly to a print on aluminum? I know it can be done, but I'm having trouble finding any specifics.