Alexandrite engagement rings? Absolutely! Diamonds may be a girl's best friend, but Alexandrite engagement rings are a unique, original, and a far more affordable choice. The birthstone of June, Alexandrite is an amazing and mysterious stone. A created alexandrite ring is a unique and entertaining attention getter. Once considered more valuable than diamonds, a peridot ring is a must have. This "gem of the sun" is the birthstone of August and is a beautiful match for the lush green tapestry of late summer.