Abstract
We present an inquiry-based lab approach thatenabled undergraduate students to synthesize ruby and sapphiregemstones not only as nanocrystals but also as macroscopic crystalsthrough assisted microwave combustion synthesis and a fluxgrowth method. This approach is highly involving for the studentsand can be used as a support to easily train them on moretheoretical knowledge such as spectroscopy, light properties (e.g.,light scattering), binary diagrams, etc. and connect them tolaboratory experiments. The trial-and-error process that led to thefinal procedure was spread over a few years and showed howinvolvement, imagination, and curiosity can remain high even in amultiyear process involving different generations of students.