The English name of garnet: ‘Garnet’, comes from the Latin ‘Granatum‘, which means “seed, grain”. This is because garnet crystals have the shape and color of a pomegranate. As the birthstone for January – garnet symbolizes truth, friendship, and fidelity.

Due to the different mineral elements contained in garnet, the final color of garnet is also very different. The well-known colors of garnet are red, purple, yellow-red, brown, dark red, and purple. The chemical formula of garnet is A3B2[SiO4]3, where A represents the second-order calcium, magnesium, iron, manganese, and other cations, and B represents trivalent aluminum, iron, chromium, manganese, and other cations. It not only has rich colors but also has relatively high hardness. High (Mohs hardness 6.5~7.5), and has starlight, discoloration, and cat’s eye effects.

What You Should Know About Garnets

A Beautiful Gemstone

Table of Contents

The history of Garnet

Garnet has a long history. Already a very common gem during the Bronze Age, the ancient Egyptians used garnets to beautify their clothing. Bracelets decorated with garnets also appeared in ancient Greece in the 4th century BC. Archaeologists have discovered red garnet necklaces in ancient Egyptian pyramids. After research, it has been concluded that this string of necklaces has existed for thousands of years as a funerary object for pharaohs. Among them, the cabochon red garnet (carbuncle) is considered to be a gift from God to King Solomon. One of the four gems. From the Renaissance to the Victorian era, red garnet produced in Bohemia was the mainstream jewelry at that time.

Unlike minerals such as beryl or corundum, which are formed from trace elements in a single species and different colored varieties, garnet comes in different species and has never been found in its pure state. They are always mixed with other garnet varieties. Garnets are known as solid series or mixtures. Some of these compounds have distinct characteristics and are themselves considered varieties of garnet. What makes them all garnets is the same crystal structure and similar properties.

Garnet Varieties

Almandine

The name almandines come from Alabanda in Asia Minor, where garnets were processed in ancient times. Almandine has a variety of colors, and its chemical composition is Mg3Al2(SiO4)3, in which part of the magnesium element will be replaced by iron and manganese ions. Among them, the mixture of almandine and pyrope is a dark red to brown-red translucent crystal, some of which are precious, and are dark red and transparent. It is the most common deep red garnet in the gem world. A small amount of pyrope produced in kimberlite has a color-changing effect.

Almandine

Spessartine

Spessartite, also known as fantasite, is a relatively rare garnet. This kind was first discovered in Bavaria, Germany. If classified according to quality, the most famous origins are the Rutherford (Rutherford) mining area in Armenia and Virginia in the United States.

The colors of spessartite are brownish red, rose red, yellow, brownish yellow, and so on. One of the fine spessartines is similar in color to Fanta drinks and is called “Fanta Stone”.

Fanta stone has high clarity and is bright and eye-catching in sunlight. Its interior is acicular inclusions arranged in parallel, which can present a cat’s eye effect.

Spessartine

Grossular garnet

The chemical composition of calcium aluminum garnet is Ca3Cr2(SiO4)3, in which the chromium ions are usually replaced by a small number of iron ions, which have been recorded since the 16th century. “Tsavorite” also belongs to grossular garnet, the chemical name is chromium vanadium grossular garnet because it contains trace amounts of chromium and vanadium elements. Its emerald green dazzling color is pleasing to the eye. The main producing area is Sri Lanka, and the common colors of grossular garnet in Mexico, Brazil, Canada, and other places are green, yellow-green, yellow-green, yellow, maroon, and milky white.

Grossular garnet

Andradite

The main chemical composition of the dendrite is Ca3Fe2(SiO4)3, and its colors are: yellow, green, brown, and black. When the iron ions are replaced by chromium ions, it becomes what is known as a demantoid. Android garnet with too many titanium ions is known as black garnet.

Andradite

Pyrope

The chemical composition of pyrope is Mg3Al2(SiO4)3, in which a small amount of Fe and Mn are commonly substituted for Mg. Magnesium-aluminum garnet is a magnesium-aluminum garnet with a transparent structure. The color varies from light maroon to lavender. This gemstone was first discovered in the České středohoří mountains in Bohemia. High-quality pyrope, few inclusions, tends to be pure red, rarely brown

Pyrope

Hydro gross garnet

The chemical composition of calcium aluminum garnet is Ca3Al2(SiO4)3-(OH)4. It is mainly green, and there is also a small amount of blue-green, white, colorless, and pink. Produced in Qinghai, China. Named for its emerald green color, it has a greasy luster, and those with dark green emerald spots on a white background are of higher value.

Hydro gross garnet

The various garnets share common properties at the molecular level. Normaltan Jewelry tried to summarize the chemical formula of garnet below:

Almandine: Fe3Al2Si3O12

Grommel Garnet: Ca3Al2Si3O12

Hydrogrossular: Ca3Al2(SiO4)3-x(OH)4x

Magnesium Garnet: Mg3Al2Si3O12

Spessartine: Mn3Al2Si3O12

Perovskite: Ca3Cr2Si3O12

Although their chemical formulas are different, their basic structures are similar. Garnet crystallizes in an isometric system. The most common forms are trapezoids and dodecahedrons, but may also be blocky, granular, and tumbled pebbles.

About the color of garnet

(for reference only)

Care of Garnet

Clean the garnet with warm water, detergent, and a soft brush. Avoid using excessive heat.

The above is the knowledge of garnet collected by Normaltan Jewelry for you, hoping to help you further understand this colorful and beautiful gemstone.

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