The only gemstones made by living creatures, rare NATURAL PEARLS are produced by mollusks who layer calcium carbonate around a microscopic irritant. Most pearls used commercially today are FRESHWATER PEARLS, cultured or farmed by implanting a grafted piece of shell into freshwater pearl mussels. SHELL PEARLS, also known as simulated or replica pearls are made from mother-of-pearl. Pearl is the birthstone for June.
Most often reddish in color, garnets (rock-forming minerals with a crystal structure) are actually a family of 15 distinct minerals in colors of every shade with the exception of blue. Garnets have been used as gemstones for thousands of years, with 5 distinct types being most typically used. The most popular garnets are pyrope (usually dark red) and rhodolite (raspberry red or purplish-red). Garnet is the official birthstone for January.
The most valuable gem variety of crystalline quartz, amethyst ranges in color from pale lilac to deep reddish purple. The official birthstone for those born in February, amethyst is said to help maintain calm and composure.
One of the most abundant minerals in the Earth's crust, quartz displays the greatest profusion of colors, patterns, and textures of any mineral. Gems cut from individual quartz crystals include amethyst, smoky quartz, rock crystal, citrine, and rose quartz. Finely grained quartz, which ranges from translucent to opaque, is typically carved or cut as cabochons or beads.