In the first of a 3-part series, Treasures of Earth, Nova explores the fascinating science of gems.

Their beauty has captivated us for millennia. Their cost can be extraordinary – some are even considered priceless. Precious gems like diamonds, rubies, emeralds, opal, and jade are the ultimate treasures of the earth, and each one is made from a specific – and often torturous – recipe of chemistry, pressure, and heat. The secrets to their sparkle, color, and even strength lie deep inside the gems themselves… but could they also hold clues to one of the most enduring mysteries in the field of geology?

Watch it tonight at 10pm on WGBH 2. More Airings