Crystal glass and cubic zirconia are both used as stone simulants, but the comparison stops there. CZ has a higher refractive index and significantly greater hardness. It outperforms glass optically and holds up where glass doesn't.
The Perfect Gift
Emerald's place at May is one of the older and more intuitive birthstone designations in the Western tradition. Its deep green has resonated with spring's renewal across centuries of writing, and the association appears in ancient sources long before the birthstone standardization made it official.
A Storied Heritage
Cleopatra understood that a stone carved with your own likeness and distributed to the people you need to impress is both a gift and a statement, the emerald doing double duty as personal adornment and diplomatic instrument.