Titanium:sapphire laser as an excitation source in two-photon spectroscopy.
Each of these enamelled plates is surrounded by blue sapphires and pearls in raised filigree settings.
Nevertheless, diamonds, rubies, sapphires, and emeralds still have a reputation that exceeds those of other gemstones.
At that time, 95% of all the world's sapphires were being heated to enhance their natural color.
Blue sapphires are evaluated based upon the purity of their primary hue.
Purple sapphires contain trace amounts of vanadium and come in a variety of shades.
The most valuable blue sapphires are called cornflower blue, having a medium-dark violet-blue tone.
In the case of manufacturing rubies or sapphires, this material is alumina.