These are lab created laser rubies grown for use in the Strategic Defense Initiative, aka 'Star Wars' program, in the 1980s. Like all rubies they have a high hardness of 9, great brilliance and glow red under UV.
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 for gem usage as well.
Back in the 80s the US government spun up the SDI (Strategic Defense Initiative) program, the idea being to create powerful defenses against nuclear weapons using whatever wacky sci-fi ideas people could come up with--because of this the media often called it the 'Star Wars' program. One idea was to make powerful lasers that would shoot missiles right out of the sky en route, and because of that they grew a lot of laser ruby and stockpiled it for future use. When the SDI was finally wound down there was a lot of this stuff lying around which was surplused off and often made it into the hands of faceters. Unfortunately I missed out on all of that on account of being born that year, but we've been able to buy a few old collections that contained some of this material. We can't be 1000% certain of the provenance because it wasn't specifically labeled as government material but it was labeled as laser ruby and is from exactly the right time so I would call it 99% certain.
This material cuts super bright, neon pink stones with a ton of scintillation and super bright fluorescence which gives them an extra pop. They are great for any lover of science, fluorescence or the color pink!
