Among the twelve commonly recognized modern birthstones, they range vastly in rarity and price from such gems as reasonably priced peridot for August, to the rubies, sapphires, diamonds, and emeralds. Two of the pricier stones, diamonds, and emeralds, are found in the trio of birthstones of spring: Marchs aquamarine, Aprils diamond, and Mays emerald.

Like all birthstones, the history of aquamarine is attached to fable and legend, and over time has become associated with particular qualities. Birthstones are generally thought to bring some sort of good fortune to the wearer, or at least protect them from bad, and this trait is usually narrowed down more specifically depending on the gem. In the case of aquamarine, as its name suggests, it is thought to be protective of sailors, and even more powerful when submerged in water. Also like the sea, aquamarine is blue, sometimes with green in it. Clear blue aquamarine is more valuable than the mixed color, and darker blues are more rare as well.

Most people are more familiar with Aprils birthstone, the diamond. Diamonds are unique in many ways, which only add to their value. First, diamonds are composed of only one element, carbon, whereas other gemstones are combinations of many elements which come together to create minerals. Second, diamonds are the hardest substance on earth. The value of diamonds is based on a well defined system; you have probably heard of the 4 Cs. The first C is clarity. As with most gems, the clearer the gem, the more valuable it is. This means there are no (or at least very few) impurities in it. The second C is cut, and unlike clarity, is controlled by the craftsman. Diamonds come in many cuts, such as round, pear, and princess. The shape of the cut determines how brilliant the diamond is because it determines how many differently angled surfaces (facets) there are to reflect light. The third C is color. While yellow diamonds have become more trendy in recent past, colorless diamonds remain the most valuable and as such, the most sought after. Finally, there is carat, the weight of the diamond.

As anyone who has seen The Wizard of Oz can tell you, Mays birthstone, the emerald, is green. It is a form of the mineral beryl, as is the above mentioned aquamarine. While generally spoken of regarding diamonds, the four Cs can also be applied to explain the value of different emeralds. Representative of its timing in the birthstone chart, emeralds symbolize the brightness and promise of spring.