Noah is said to have recognized garnet's inner fire and used it as a "lamp" to reflect light on the bow of the Ark. It is difficult to find any gem whose history can go back any further than that.
Garnets have been used in jewelry and for other decorative purposes for thousands of years, dating back as early as 3100 BC when Egyptians valued garnets as beads for pharaoh's necklaces and buried them in tombs with mummies. Carved garnets adorned signet rings used to stamp wax seals in ancient Rome, and red garnets were popular among clergy and nobility in the Middle Ages from around 475 to 1450 AD. A recently discovered hoard of medieval treasure in Great Britain contained armor encrusted with inlaid garnets. Around 1600, the beloved "Bohemian" pyrope garnets of Czechoslovakia gave garnet a boost of interest in Victorian and other jewelry that lasted until the beginning of the 20th century. Slices of garnets have even been used in church windows.
Today, orange (spessartite and hessonite) and green (demantoid and tsavorite) garnets have increased in popularity and availability allowing them to join their red cousins in the jewelry marketplace beyond just being collector's stones. Rarer still are the color change garnets, some of which feature a rare bluish hue.
According to mineralogists, no garnet is ever pure in nature, so garnet species mix to create garnet varieties with a wider range of colors and characteristics. The results are happy accidents like rosy rhodolite and sparkling green tsavorite, and color change varieties that are a combination of pyrope and spessartine along with minor accounts of other rare garnets. The possibilities seem endless and several new varieties have been discovered in recent years.
Garnets are also known for the different regions in which they are mined. Mali garnet, discovered in Mali, Africa in the 1990s is a grossular-andradite. It is typically yellow, green or brown. Gypsy rose garnet discovered in Tanzania's Umba Valley is an attractive orange-red garnet that is different because of its unusually high grossular content (7.0-8.5%). Umbalite is a type of rhodolite garnet originating in this same region.
Garnets usually form in dodecahedrons, which is a complex shape with 12 equal diamond-shaped sides. These often exhibit a distinctive soccer ball appearance.