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. As the gem of peace and tranquility, amethyst is mesmerizingly beautiful. A durable and affordable gem, an amethyst ring is excellent for every day wear. Pink tourmaline is a birthstone of October, along with opal, and is a truly special gem. The deep rosy color of a pink tourmaline ring will be sure to attract attention.