These are lab created blood red rubies created by the czochralski process. Like all rubies they have a high hardness of 9, great brilliance and glow red under UV.
These rubies are a rich blood red, likely grown with a touch of iron or nickel added to reduce the purplish cast that pure chromium rubies can have, giving a richer blood red color. This ruby was grown by the Czochralski method, an advanced growth technique that produces more perfect crystals with purer chemistry than the typical stones used in jewelry. I don't know for sure what this was grown for but it was likely a technical application like high end watch cases. Fortunately the crystal had a few bubbles and I was able to get it instead and trim out clean pieces.