GARNET
When thinking of garnet gemstones, most people think of red garnet. Garnet most commonly occurs in red, and the origin of the name “garnet” lies in this deep red hue. The name “garnet” comes from the Medieval Latin word, “granatum”, which is an adjective meaning “dark-red”. It is thought that this adjective could have been extracted from the word “pomegranate”, due to the color of the seed coats or shape of the seeds. However, the word could also have come from another Medieval Latin word; “granum”, referring to red dye. The use of red garnet dates back thousands of years, when it was used by Egyptian pharaohs for both decorative and ceremonial purposes. The ancient Romans also wore garnet rings and traded garnet gemstones.
Garnet is a gem group that occurs in over twenty varieties. Of these varieties, six main types are used as gems. These are pyrope, almandite, spessartite, grossularite, andradite and uvarovite. Large deposits of red garnet were discovered in Bohemia (Central Europe) around the 16th century, which became the focus of the jewelry industry in the area. Bohemian garnet from the Czech Republic continues to be mined today. Although red is the most commonly occurring color, garnet occurs in almost every color.
Garnet Color
Garnet is available in a veritable plethora of colors, such as yellow, orange, peach, green, red, purple, blue (rare), brown and pink. However, the most commonly occurring color is red and the rarest is blue. Garnet also occurs in color change varieties, which exhibit a different color depending on whether they are viewed in incandescent or natural light. The rarest color change garnet appears blue in daylight, and changes to purplish-red under torch light. Other color change garnets are green, beige, brown or gray in daylight, and change to reddish or purplish-pink under incandescent light. The color of garnet is the most important quality factor.
Garnet Clarity and Luster
Garnet exhibits a vitreous (glassy) luster. Demantoid garnet, a rare green variety of andradite, has a high refractive index and is prized for its brilliance and adamantine luster (diamond-like) luster. In fact, the name, “demantoid”, comes from the German word “demant”, meaning “diamond”, in reference to its luster. Garnets are generally clean stones, however, almandine garnets sometimes have asbestos fibre inclusions. These inclusions cause asterism (a star effect), which is treasured due to its rarity. Additionally, some orange garnet, such as spessartite and hessonite tends to exhibit eye-visible inclusions. Russian demantoid garnet is highly for its distinctive, horsetail-like inclusions.
Garnet Cut and Shape
Garnets are extremely versatile and can be cut in any fashion and shape. Red garnet tends to be cut into standard shapes, whereas valuable garnets that are not often found in large sizes, such as tsavorite and demantoid, are cut into shapes that retain the most carat weight.
Source: GemSelect