Not only for August birthdays, peridot is a popular alternative to emerald as it has a paler, subtler appearance. The pastel hued crystal is placed into a rub over setting and is 4mm. The stud dimensions are 5mm high x 5mm wide x 4mm deep and weigh 1g for the pair, so they are pretty light. The gold plated sterling silver goes beautifully with the peridot stone, especially if you're looking for a pair of studs for christmas!