was reading about aluminium oxynitride, hard as sapphire, Raytheon found in the 80s, now made by Surmet. it's everywhere in mil grade systems now, bulletproof windows, armor, domes, lenses, etc.
what does one think it costs roughly? any avionics screen in a gull sports it yet? what other transparent materials in use in the gulls? bit gloomy my only sapphire thing yet was stolen some yrs back, was a watch..
thanks,
rc