SDI/'Star Wars' Laser Ruby Rod Segments, Cold War Ruby

These are rod segments of Star Wars (aka 'Strategic Defense Initiative') laser ruby from the 80s.  They were likely sawn from laser rods before final polishing and coating.This is the most classic gem produced by science: laser ruby. While material of this color would be called 'pink sapphire' in a gemological context, in laser science all corundum doped with chromium is considered ruby (in contrast to pink laser sapphire which is doped with titanium). In a laser this material would be cut into a cylinder, charged up with photons from the sides and emit a beam of coherent light out of the end--in fact the very first laser was built with a ruby. As you would expect for this requires a very high standard of chemical purity and structural perfection--when energizing a crystal imperfections tend to heat up and explode. Czochralski pulling ensures that these stones have perfect crystal structure, high chemical purity and strong, even coloration, which coincidentally makes them exceptional f