Unveiling the Diverse World of Garnets: A Comprehensive Guide to 9 Varieties
Garnets, often synonymous with the deep red gemstone of January's birthstone, are a diverse group of minerals with a rich palette of colours and unique properties. This family of gems is not just limited to the classic red but spans a spectrum of hues, each variety offering its own distinct charm and allure. Here's an in-depth exploration of nine fascinating types of garnets, revealing this gemstone family's hidden beauty and diversity.
The garnet family is a fascinating and diverse group of silicate minerals cherished for thousands of years for their beauty and perceived metaphysical properties. Here's an in-depth look at the Garnet family as a whole:
Composition and Structure
Chemical Formula: Garnets have a general chemical formula of X₃Y₂(SiO₄)₃, where X and Y are various metal ions. The diversity in the garnet group arises from the different combinations of these metal ions.
Crystal System: Garnets crystallize in the cubic system, typically forming dodecahedral or trapezohedral crystals. Their crystal structure is responsible for their characteristic shapes and high symmetry.
Hardness: Garnets typically range between 6.5 and 7.5 on the Mohs scale of hardness, making them durable enough for various types of jewelry.
Refractive Index: They generally have a high refractive index, contributing to their brilliant sparkle.
Lustre: Garnets typically have a vitreous (glass-like) lustre.
Cleavage: Garnets lack cleavage, which means they do not break along defined planes and are more resistant to fracturing.
Colour Range: Garnets are renowned for their extensive colour range, covering almost every colour, including red, orange, yellow, green, purple, brown, black, and even colourless. The colour is often influenced by trace elements such as iron, chromium, and manganese.
Symbolism and Uses
Historical Significance: Garnets have been used for thousands of years. They were popular in ancient Egypt, Rome, and Saxon and Viking artifacts.
Symbolism: They are often associated with love, friendship, light, and vitality.
Uses: Beyond jewelry, garnets are used in industrial settings for cutting and sanding.
Care and Maintenance
Cleaning: They should be cleaned with warm, soapy water and a soft brush. It's generally advised to avoid ultrasonic and steam cleaners.
Handling: While relatively hardy, they should be protected from sharp blows and extreme temperature changes.
Ethical and Sustainable Aspects
Sourcing: Knowing where your garnets come from can help ensure they are sourced ethically. Some garnet mining practices are more sustainable and ethical than others.
Garnets offer a beautiful and diverse range of options for jewelry, combining historical significance with modern appeal. Their variety in colour and type means there's almost certainly a garnet that can fit any design or style preference.
A Cheat Sheet of Garnet Species and Sub-Species
9 Types of Garnet You Should Know
1. Grossular Garnet: A Spectrum of Nature's Best
Grossular garnet is technically a group that features several varieties of garnet covering various colours. There are colourless varieties and green, yellow, orange, red, brown, and black varieties. Sometimes, a variety of grossular garnets may be gray, and some are considered white.
Several gem types of green garnets are in the grossular group, with tsavorite being the best-known garnet variety. For warmer colouring, hessonite is usually the most widely known, particularly the golden orange versions of the stone.
The Mali garnet is the most recent discovery within the group, initially found in 1994. It's exceptionally rare and has yellow colouring with hints of light green, giving it a sense of play-of-colour when properly faceted.
Another incredibly rare version is the Leuco garnet. It's a colourless version that can resemble a diamond, depending on the clarity. Some versions are also gently tinted, giving the stone a hint of yellow or green.
Nicknamed the “cinnamon stone,” the hessonite is one of the garnet types with an earthier hue. These garnet stones colours range from goldenrod to red, with some orange and red versions having tints of brown.
Usually, the vibrant golden orange hessonite garnet gemstones are the most popular. They often look like honey, though an internal fire shines orange. Additionally, a hessonite garnet with a high degree of clarity is preferred, as those with inclusions can look muddy or oily.
As with most other garnets, high-quality versions are typically faceted. However, those with inclusions may become cabochons instead.
3. Tsavorite Garnet
Tsavorite is a relatively new discovery. The first ones weren't unearthed until 1967 and are exceptionally rare. In many cases, that makes tsavorite an expensive stone.
The tsavorite garnet is a grossular garnet by composition; it's simply a version found in a specific place: Tsavo National Park in Kenya. It's only mined in certain parts of East Africa and is prized in the gem world due to its natural green colouring.
Green tsavorite contains chromium and vanadium, which give the stone its striking hue. Most specimens are a deeper green, though some are incredibly bright and vibrant. The latter versions are the most prized, but all types are popular.
This green garnet stone usually has excellent colouring and clarity. Plus, the lustre is often exceptional. As a result, it's most commonly faceted when used in jewelry.
4. Umbalite Garnet
One of the rarer garnets, umbalite, comes in various hues. Initially discovered in the 1960s, the umbalite garnet most commonly comes in shades of red, purple, pink, and brown, though some may lean yellow or orange.
When it comes to one of the most desirable colours of umbalite, there are blue versions available. This blue garnet stone wasn't discovered until 2017 and is exceptionally rare. Generally speaking, it's a teal blue garnet gemstone. Depending on the lighting, it can have colour-changing characteristics, transitioning from teal blue to green.
Umbalite garnet is usually faceted since it has strong clarity and a good fire. However, if found with rutile crystal inclusions, it may be turned into a cabochon to capture a cat's eye effect.
5. Spessartite Garnet
Spessartite – also called spessartine by some – is a striking garnet first discovered in Germany. It's known for its bright orange colouring, a shade that often resembles a pumpkin. While some versions lean more toward yellow or red, and some have a brownish tint, most people who want a spessartite garnet are after the orange shade.
The most popular orange spessartite garnet is occasionally called Mandarin garnet, which is technically a tradename. Usually, those stones have the most vibrant orange colouring, bright enough that some refer to the hue as electric orange.
Spessartite garnets with high degrees of clarity are usually faceted. However, those with fibrous inclusions may become cabochons, as the inclusions can create a cat's eye effect. Some Spessartite garnets can even change colour.
Another rare garnet species, rhodolite, stands out due to its unique hue. While the colours of garnet usually fall in the red or green family, rhodolite is a pink garnet. It leans pink, rose, purple, or violet, with many versions being a shade close to raspberry.
Along with intriguing colouring and solid clarity, rhodolite garnet is tough. That makes it suitable for everyday wear, which is excellent if you're looking for jewelry stones. Its high dispersion creates a breathtaking fire, too, which is why most rhodolite garnet is faceted if it's gem-quality.
In some cases, rhodolite may contain rutile crystals. When that happens, the piece can have a cat's eye effect. Those gems are usually turned into cabochons to highlight that unique characteristic.
The almandine red garnet is the most common stone on this list, so it's highly accessible. It usually contains less iron and more magnesium, resulting in a deep, rich red colouring. However, the garnet almandine can be black sometimes, resulting in an incredibly striking gemstone. It may also exhibit hints of purple or brown.
While almandine is faceted when the stone offers sufficient clarity, it's also turned into cabochons frequently. The almandine gem is called a carbuncle when shaped in that fashion.
In most cases, almandine is an inexpensive garnet, which makes it perfect for the budget-conscious. However, gem-quality almandine garnet versions with high degrees of clarity can be costly, so keep that in mind.
Of all the types of garnet gemstones, pyrope is the only one that's practically always red in natural specimens. The red can range from incredibly vibrant to deep dark red – depending on its precise chemical composition – and often resembles a ruby, which makes it highly desirable.
There are rare cases where a piece of pyrope ends up colourless. When this occurs, it's an incredibly valuable version of the stone, primarily because a specimen of that nature isn't found often.
Pyrope also typically has exceptional clarity. It rarely has flaws or inclusions, giving it high transparency. As a result, pyrope is frequently faceted, though there are also cabochons around.
9. Demantoid Garnet
The demantoid garnet is the most expensive garnet due to its rarity. Typically, the demantoid garnet stone colour is a lighter green, often having hints of yellow or brown. However, the pure green versions are the most highly coveted, making them the most valuable overall.
Generally, the shade of green is a tad less vibrant than what you find with peridot. Some may describe it as minty. Others may consider it closer to spring green. When there's more yellow, it can be closer to a delicate version of lime, while it may look a bit sage-toned if there are hints of brown.
In some cases, fibrous inclusions form in a "horsetail" configuration. While inclusions usually don't boost a stone's value, this horsetail increases the price of demantoid garnet.
Frequently Asked Questions About The Garnet Family
Is a garnet expensive?
Variability in Price: Garnet prices vary widely depending on the type, size, colour, and quality. Some types, like Almandine, are relatively affordable, while others, like Demantoid and Tsavorite, can be quite expensive.
Factors Affecting Price: Rarity, colour intensity, clarity, and cut all play a role in determining the price of a garnet.
Who should not wear garnet?
Astrological Beliefs: In astrology, it's believed that certain gemstones may not be suitable for everyone, depending on their zodiac or other astrological factors. However, these beliefs are not scientifically backed.
Practical Considerations: People with active lifestyles or those who frequently work with their hands might want to consider the durability of garnet (especially softer varieties) in their jewelry.
What is the rarest colour of garnet?
Blue Garnet: The rarest colour of garnet is blue, which changes colour from blue-green in daylight to purplish-red under incandescent light. This type is extremely rare and valuable.
How can I tell what type of garnet I have?
Professional Assessment: The most accurate way is to have it evaluated by a gemologist.
DIY Methods: You can make an educated guess based on colour and transparency. For instance, if it's a vibrant green, it could be a Tsavorite or Demantoid.
What is the difference between almandine and pyrope garnet?
Almandine: Typically deep red to reddish-brown, often with a tinge of violet. It's the most common type of garnet.
Pyrope: Known for its transparency and vivid red colour, often without any brownish or orange tone.
How can you tell if a garnet is grossular?
Colour Range: Grossular garnets range from colourless to yellow, golden, orange, scarlet, and green. The green variety (Tsavorite) is particularly prized.
Transparency and Luster: Grossular garnets often have a vitreous lustre and can be transparent to translucent
Is tsavorite more rare than emerald?
Rarity: Tsavorite is rarer than emerald. It's found in fewer locations, and its deposits are usually smaller.
Comparison: Despite its rarity, tsavorite is often less expensive than emerald due to lower demand and less historical significance.
What is the difference between spessartite and spessartine?
Terminology: "Spessartite" and "Spessartine" refer to the same type of garnet. The terms are used interchangeably in the gemstone industry.