Single-crystal corundum rod grown for use as the gain medium in solid-state ruby lasers. These rods are manufactured to a much higher optical purity than typical synthetic ruby used for faceting or cabbing, with tightly controlled chromium content that produces the vivid magenta coloration. The ridged surface is intentional and was designed to improve light distribution when the rod is pumped by a flashlamp inside a laser cavity.

Ruby lasers operate at 694.3 nm, a deep red wavelength that was historically used in Q-switched medical and aesthetic systems, including early tattoo-removal units. Although most modern devices use Nd:YAG, ruby laser rods are still produced for replacement parts, research applications, and educational demonstrations.

These rods are supplied unfinished, with ends left flat and uncoated. They can be repurposed for optical experimentation, cut into faceting rough, or held as a collectible piece of laser history

Approximately 10 x 10 mm at the clear round ends and 9 x 5 mm through the corrugated pink centers.  They are approximately  17.5 cm long

Price of $48 is for a single rod