Hessonite
Nicknamed the "cinnamon stone", hessonite is a variety of grossular garnet and comes in two colors, golden and cinnamon. A perfectly colored hessonite is a bright golden orange that resembles a combination of honey and orange with an internal fire. Some hessonites have tints of red and brown with cinnamon appearance. Hessonite is common in the gem gravels of Sri Lanka and practically all hessonite is obtained from this locality, although it is also found in Africa. While the clearest gems are most prized, inclusions in hessonite are common, with unique toffee-like streaks giving hessonite an oily or even glass-like appearance.
Hessonite Classification
| Common Name |
Hessonite |
Hessonite Optical Properties
| Refractive Index |
1.74 typical |
| CCF Reaction |
None |
Hessonite Characteristic Physical properties
| Specific Gravity |
3.57 |
| Toughness |
Good |
| Inclusions |
Stubby, rounded included crystals. Shows oily, "heat wave" or "scotch in water" effect. |
| Stability |
Good |
Mali Garnet
Mali garnet is one of the latest discoveries in the garnet family. This attractive and very interesting rare mixture of andradite and grossular was only discovered in late 1994 at the Sandar Mine in Mali's Kayes region (Diakon Arrondissement). Extremely rare, Mali garnets are a bright, uniform light yellowish green color.
Mali Garnet Classification
| Common Name |
Mali Garnet |
Mali Garnet Optical Properties
| Refractive Index |
1.752-1.779 |
| Fluorescence |
SWUV: Inert
LWUV: Inert |
Mali Garnet Characteristic Physical properties
| Specific Gravity |
3.64 |
| Toughness |
Good |
| Inclusions |
Many Mali garnet stones are inclusion free but sometimes small mineral crystals and fingerprints are found along with parallel growth planes. |
| Stability |
Good |
Leuco Garnet
Leuco garnet is the colorless variety of grossular garnet. The colorless variety is extremely rare. Known specimens have come from Myanmar and Sri Lanka.
Leuco Garnet Classification
| Common Name |
Leuco Garnet |
Leuco Garnet Optical Properties
| Refractive Index |
1.74 typical |
| CCF Reaction |
None |
Leuco Garnet Characteristic Physical properties
| Specific Gravity |
3.57 |
| Toughness |
Good |
| Inclusions |
Might contain mineral inclusions or healed fractures |
| Stability |
Good |
Mint Garnet
Mint garnet is the pale green variety of grossular garnet that gets its color from trace amounts of vanadium and chromium. Gemstones are typically under 1 ct. It is indicator gem for tanzanite and has been found in Tanzania, Kenya, and Madagascar. It has the nickname “UV garnet” because most stones florescence a peachy orange in Long Wave Ultraviolet light.
Mint Garnet Classification
| Common Name |
Mint Garnet |
Mint Garnet Optical Properties
| Refractive Index |
1.74 typical |
| CCF Reaction |
None |
Mint Garnet Characteristic Physical properties
| Specific Gravity |
3.57 |
| Toughness |
Good |
| Inclusions |
Rounded mineral inclusions, silk |
| Stability |
Good |
Rosolite, Landerite or Xalostocite
Rosolite which is sometimes called landerite or xalostocite is found in Sierra de Cruces, Mexico. It is the translucent to opaque variety of grossular garnet found in marble.
Rosolite, Landerite or Xalostocite Classification
| Common Name |
Rosolite, Landerite or Xalostocite |
Rosolite, Landerite or Xalostocite Characteristic Physical properties
| Specific Gravity |
3.57 |
| Toughness |
Good |
| Inclusions |
Included |
| Stability |
Good |
Tsavorite
Tsavorite is one of two green varieties of garnet, though arguably the more important of the two. Especially in smaller sizes, tsavorite creates competition for emerald because it is less included, rarely treated and more durable. Like some emerald and green tourmaline, tsavorite garnet owes its green hues to the presence of vanadium and chromium. First discovered in Tanzania in 1967 and a few years later in Kenya, tsavorite's name pays homage to the nearby Tsavo National Park.
Tsavorite Classification
| Common Name |
Tsavorite |
Tsavorite Optical Properties
| Refractive Index |
1.74 typical |
| CCF Reaction |
Some stones may appear pink or red |
Tsavorite Characteristic Physical properties
| Specific Gravity |
3.57 |
| Toughness |
Good |
| Inclusions |
Tsavorite garnet is a Type II clarity stone. Stones will sometimes have feathers, fingerprint inclusions, needles, asbestos fibers and small graphite platelets |
| Stability |
Good |
Hydrogrossular Garnet
Hydrogrossular garnet is typically translucent to opaque and is usually available as cabochons, but on rare occasion may be found as transparent, faceted gemstones. Generally seen as green to blue-green, pink, white, and gray, this gemstone may contain small dark gray to black inclusions and may look similar to jade if opaque. Hydrogrossular is a variety of grossular garnet where hydroxide partially replaces silica.
Hydrogrossular Garnet Classification
| Common Name |
Hydrogrossular Garnet |
Hydrogrossular Garnet Optical Properties
| Refractive Index |
1.72 typical |
| CCF Reaction |
Green: possibly pinkish |
Hydrogrossular Garnet Characteristic Physical properties
| Specific Gravity |
3.13 |
| Toughness |
Good |
| Inclusions |
Might have black magnetite inclusions that resemble pepper. |
| Stability |
Good |
Brown 
Yellow 
Green 
Red 
White 
Gray 
Black 
