The Difference Between Rubies and Garnets
What do California rubies, Arizona rubies, and Elie rubies all have in common? None of them are actually rubies; they're garnet! More specifically, they're pyrope garnet, a type of garnet known for its red hues. If it looks similar enough to ruby to give it so many misnomers, you might wonder, what are the differences between rubies and garnets?
Ruby and garnet can be told apart by their differences in color, light reflections, hardness, and cost. To help you decide which one is right for you, we've put together a guide to compare and contrast these two red gemstones.
Fun Facts about Garnets and Rubies
Before we get to the guide, here are some interesting trivia facts that might surprise you about garnets and rubies.
Interesting and Weird Ruby Facts:
- Rubies appear to glow in the sunlight. This isn't just an illusion – electrons in rubies have fluorescence; they absorb some of the sun's energy from UV rays and release it as they return to the ground state. The glow you see in rubies is actually photons emitted from electrons in the gem!
- In 1960, Theodore Maiman invented the world's first laser, called the "ruby laser," which worked using the red fluorescence light emitted by rubies.
- Tsar Ivan IV ("Ivan the Terrible") believed that gemstones could heal him in various ways. He believed that rubies could promote heart health and that they could increase his memory and mental clarity.
- In the Middle Ages, people believed ground rubies could cure liver ailments and counteract poison.
- Judy Garland's ruby slippers in The Wizard of Oz were made from red sequins, but in 1989, American jeweler Harry Winston created a pair made of real rubies to commemorate the film’s 50th anniversary. These slippers feature 4,600 rubies totaling over 1,300 carats, worth $3 million.
Interesting and Weird Garnet Facts:
- It is the state mineral of Connecticut and the state gemstone of New York. Idaho also has garnet as its state gemstone, but only the specific variation called star garnet (garnet with rutile asterisms).
- Arizona garnet is mined by ants! These gems come from Northern Arizona on the Navajo reservation, found along the edges of anthills. When the ants dig their homes underground, they bring up rocks that get in their way, including these garnets. They accumulate small piles of garnets that you can find when it rains.
- Green demantoid garnets were popular in Russia because Peter Carl Fabergé made jewelry with them and Tsars wore them.
- There are reports of the Burusho people using garnet bullets to fight the British troops in northern Pakistan between 1889-1892.
- Ancient Romans wore signet rings made of garnet that featured intaglios that were used to stamp wax for important documents.
Rubies vs Garnets Geology
Both gems come in stunning shades of red. Despite the similar color, they have different structures and chemical properties.
What Is a Ruby?
A ruby (the name comes from the Latin word rubeus, meaning red) is a red precious gemstone made of corundum. Sapphire is also made of corundum. In fact, rubies and sapphires have the same chemical makeup.
We don't classify rubies as red variants of sapphire due to the special geological circumstances that give it its red color.
The element chromium is responsible for the beautiful red color that all rubies have. The deepness of red in a ruby can vary: some rubies are pinkish or orange-ish while other rubies are a deep red color.
Every shade of ruby must be considered a variant of red. If the corundum is pink, orange, or violet, it's a sapphire. Rubies are so rare because it requires a specific balance of rare trace elements to form it, as well as the absence of excessive silica or iron.
What Is Garnet?
While the term "ruby" applies to a specific form of blood-red gemstone quality corundum, "garnet" refers to a group of silicate minerals. Throughout history, rubies have been cherished as gemstones, but garnet has been used in other ways. Garnet has been used as both a decorative gemstone and as an abrasive.
There are different types (called species) of garnet. All species of garnets have similar physical properties and crystal forms, but have different chemical compositions. Garnet occurs in many colors, including pinks, greens, reds, oranges, and violet.
What Are the Different Colors of Garnet?
Red garnets are just one type of the mineral’s color family. Different sub-types can have different colors. Here's a list of some of the different species of garnet and their colors.
Pyrope is the species of garnet that people confuse with rubies. It's the only species that always exhibits red coloring. Pyrope comes from the Greek word for "fire" and "eye."
Almandine is another species of red garnet. Its color can range from deep red to shades of purple.
Spessartine typically ranges from shades of brown, orange, and violet-red. The orange-yellow variant comes from Madagascar and is called the "mandarin garnet."
Grossular: Grossular garnet can be shades of green, brown, cinnamon brown, and colorless. The name grossular is derived from the botanical name for the gooseberry, grossularia. This name references the green variety of grossular garnet that's found in Siberia.
There are a few different varieties of grossular garnets, such as hessonite, rosolite, and leuco-garnet.
Tsavorite is the most highly sought-after variety. It was discovered in 1960 in the Tsavo area of Kenya and in Tanzania. It's is known for its vivid green appearance.
Only geologists and mineral specialists knew about tsavorite until 1976, when Tiffany and Co launched a marketing campaign to reach a jewelry consumer market. Finding it in gem quality is rare, especially for multiple carats.
How to Tell Rubies and Garnets Apart?
Some variations of garnet can appear a similar shade of red to some rubies. It's no wonder why some varieties of pyrope garnet use "ruby" in their trade name. Fortunately, it's not very difficult to distinguish these two types of gemstones.
Examine the Color
Rubies are usually a vivid red color. This can range from a bright, fuschia-like red, to a fiery red, to a deep dried blood color. Traditionally, the most desirable rubies are the famous pigeon's blood red.
Red garnets are usually darker than rubies and may contain hints of orange, pink, and brown. A highly polished and well-cut garnet can have a deep red shade, it's not as deep as the red in rubies. Dark red rubies will still have vivid red color, while dark red garnets have a less saturated hue.
If you hold the gems up to eye level, you may see speckles of other colors in a garnet. Rubies will be consistently red throughout, although they can have secondary hues of purple and blue. If you notice yellow or orange colors, it's a garnet.
A good way to examine gemstones is by using natural light. With natural lighting, you can examine the crystalline structures of minerals, which will affect how they reflect light. When you hold it to the light, turn it slowly in your hands.
If you hold a garnet up to natural light, it reflects a rainbow of colors, including bands of yellow and green.
If you hold a ruby to natural light, you'll see a pinkish tinge within the stone, but an absence of yellow and green. This is because the crystal structure of the ruby absorbs yellow and green and therefore won't reflect them. You may see other shades of the rainbow in a ruby.
Gemstone fluorescence is a beautiful and intriguing phenomenon that some gems exhibit. Fluorescence occurs in some gemstones that contain specific minerals with activator elements. Only 15% of minerals fluoresce.
Not every ruby shows strong fluorescence, but many of them do have both daylight luminescence and fluorescence. Part of the reason rubies seem to glow from within in natural lighting is due to their luminescence.
To test fluorescence, you would place the gemstone under a UV light.
The only garnets that exhibit fluorescents are some green garnets. Grossular garnets such as tsavorite may fluoresce a weak orange in long UV and weak yellow in short UV.
Under UV light, rubies may fluoresce brightly and appear to glow. If a gem seems to glow under UV light, even a little, it's more likely a ruby than a garnet. Burmese rubies often fluoresce brightly and exhibit fluorescence even in bright natural light.
Thai rubies fluoresce less intense fluorescence and may fluoresce in patches if they're heat-treated.
Here's a lab guide to fluorescence intensity in rubies and sapphires.
While rubies have dazzling fluorescent traits, some garnets have their own variation of color-play. Color-change garnets come from specific localities such as Tanzania. These garnets appear a strong pinkish color under warm incandescent light and a vivid purple in cooler tinted lighting.
Some blue sapphires also share this trait. It's a rare quality that's only shared by a handful of other gems, including some specimens of alexandrite, chrysoberyl, and fluorite.
Rubies tend to have more internal inclusions and flaws than garnets. While inclusions aren't usually ideal, the rarity of rubies means that the gem can still be very valuable with inclusions. Its presence of chromium causes tiny cracks and fissures within the gem, and these are considered natural facets of the gem.
When you hold garnets up to the light, they're usually more clear. There won't usually be any noticeable cracks or other flaws. You may see specks of colors, but they're not inclusions.
Hardness and Durability
On the Mohs hardness scale, rubies rank 10, just after diamonds. They are prized for their hardness and durability.
Garnets rank 6.5 to 7.5. They're a softer gemstone, but still relatively hard and durable. At 7.5, garnets are still hard enough to be a popular abrasive for industrial purposes.
Both rubies and garnets are a durable choice for jewelry you wear daily. Rubies are currently more popular as engagement ring gems, but garnets are growing in popularity as younger people seek more colorful alternatives to diamonds.
Rubies in the Rough vs Garnets in the Rough
Part of the reason people have confused rubies with garnets historically is that garnets can sometimes grow alongside rubies.
Pyrope garnets and rubies sometimes look similar when they're in the rough, but a closer look can distinguish them.
Unpolished garnets have many of the same aesthetic traits as the cut and polished ones. Unpolished rubies look quite different from polished rubies, but it's their color that gives them away. Even rubies in the rough will exhibit the deep characteristic red color that is unique to rubies.
Rubies vs Garnets: Which Is More Valuable?
Rubies are one of the rarest gemstones, and their rarity is what categorizes them as a precious gemstone. Rubies will be more expensive than garnets in most cases.
Garnets are found in abundance, but certain colors of gemstone quality can make them expensive. Tsavorite, for example, is a rare variety of garnet, and less abundant than diamonds. Nevertheless, garnets are considered semi-precious gemstones.
Gem-quality garnet is still valuable, especially compared to other semi-precious gemstones. This makes them more affordable than rubies.
Which One Is Right for Me?
If you're jewelry shopping for a red gemstone, both rubies and garnets are gorgeous options. Which one you choose will depend on your budget and purpose.
If you want a breath-taking, flashy red engagement ring, you might want to go with rubies. Their fluorescence makes them shine like fire in the sun, and their rarity makes them really unique.
Garnets are more popular for statement rings, graduation rings, promise rings, and birthstone jewelry (garnet is the January birthstone). Both rubies and garnets have historical significance and symbolism. If you prefer a more subdued but still remarkable red, red garnet can also make for a good and more affordable engagement ring.
If rarity matters and you're not set on red, tsavorite garnets are a special addition to any jewelry collection. They can make for a great conversation starter. They're also great for nontraditional weddings because they are a much more recent discovery than rubies and other species of garnet.
Whether you prefer garnets or rubies, a red gemstone makes a statement. It's no coincidence that these red gems have been so popular throughout history. The color ignites the imagination, symbolizes passion and protection, eternity, and robustness.