Brown Gemstones: A Guide to Colored Stones
When it comes to colored gemstones, color is king. Today, many customers prioritize color and are less concerned with the actual gemstone variety as long as the stone is durable enough for their purpose.
Using our guide below, you can learn about some of the most popular brown gemstones choices available today:
- Boulder Opal
- Brown Quartz
- Chocolate Opal
- Color Change Garnet
- Golden Beryl
- Hessonite Garnet
- Mali Garnet
- Opal in Matrix
- Rutile Quartz
Brown AgateBack to Top
Agate is a banded form of chalcedony quartz that occurs in many different colors and even geodes, which are rock cavities or vugs with internal crystal formations or concentric banding. Brown agate gemstones include fire agate, which is admired for its fiery iridescence; and dendritic agate; brown agate with black dendritic inclusions. Agate gems are extremely versatile and may be sold as beads, cabochons, faceted gems, agate geodes, carvings, slices or as tumbled stones. Agate geode gems and slices are particularly popular for their "raw" look. Jewelry made from agate is hard and durable enough to last for centuries, with a pleasing waxy luster and translucent to opaque clarity.
Brown AndalusiteBack to Top
Andalusite is a lesser-known gem that gets its name from Andalusia, where it was first found, though it is now found in many places, such as Australia, Russia, Canada, Brazil, Sri Lanka and the USA. It shares the same composition as sillimanite and kyanite (aluminum silicate), making all three minerals polymorphs; minerals with the same composition, but different crystal structures. Andalusite has strong pleochroism; the ability to exhibit different colors from different angles, which gives andalusite unique combinations of color.
Brown AxiniteBack to Top
Axinite is a rare, violet, blue or brown gem type composed of calcium borate silicate which is a popular collector's stone. Its name comes from a Greek word for "axe" because of its unusual, spatula-shaped crystals. Interesting phenomena of axinite include its pyro- and piezoelectric properties, meaning that it can generate an electric current when heated, cooled or exposed to mechanical stress or pressure.
Brown Boulder OpalBack to Top
Boulder opal is a valuable opal variety that is found embedded in large boulders of ironstone, in which precious opal forms in thin fissures, veins and hollows. It is also called "opal in matrix" because some of the matrix rock is preserved when the opal is removed and then cut into gemstones. The ironstone of boulder opal gemstones is opaque and brown, with a range of colors seen in the transparent to translucent precious opal.
Brown CassiteriteBack to Top
Cassiterite is a the primary ore for tin and a rare collector's gemstone composed of tin oxide that is sometimes called the "tin stone". The name, "cassiterite" comes from a Greek word meaning "tin". Cassiterite gemstones may be brown or black and have an extremely high refractive index, giving them remarkable fire and dispersion, as well as an attractive adamantine or submetallic luster. Though cassiterite is mostly a collector's stone, it is hard enough to be used for jewelry.
Brown Chocolate OpalBack to Top
Chocolate opal is a translucent to opaque opal variety from Ethiopia that forms within layers of volcanic ash in Yita Ridge; a small area northeast of the capital city, Addis Ababa. As its name suggests, chocolate opal has a distinctive chocolate brown color, which may be light- or dark-brown. Like precious opal, chocolate opal exhibits play of color and specimens with vivid and intense play of color are most valued, especially stones that display a range of colors.
Brown Color Change GarnetBack to Top
Color change garnet is one of the rare varieties of garnet gemstones and can be many different colors, including green, pink, peach, bluish, purple, reddish or brown. Color change garnet gemstones are typically a mix of spessartite and pyrope garnet and tend to shift to a warmer color under incandescent light. The most frequently seen colors in color change garnet are brownish-green or bronze under daylight and rose or pink under incandescent light, though some stones may be other color combinations.
Brown DiamondBack to Top
Diamond is composed of pure carbon and is the hardest material on earth, with a Mohs hardness rating of 10. Brown diamonds are a fancy diamond color that was not popular until relatively recently. The incredible hardness, brilliance and adamantine luster of diamond, along with clever marketing techniques for "chocolate" and "cognac" diamonds, made brown diamonds a hit. Colored diamond gemstones are graded by color intensity, with the highest saturation of color being the rarest and most valuable.
Brown EnstatiteBack to Top
Enstatite is a pyroxene mineral that is rarely found in gemstone quality. Its name comes from the Greek for "resistor", due to its high melting point. Fine enstatite is transparent and may be greenish-brown, yellowish, green, brown or colorless. Golden brown enstatite is colored by traces of iron. Since enstatite is relatively soft, it is mostly used as a collector's gemstone, or reserved for pendants and earrings.
Brown Golden BerylBack to Top
Golden beryl is a yellow to honey-colored member of the beryl family; the same group of gemstones as morganite, emerald and aquamarine. Though golden beryl is the most affordable and easily available beryl gemstone, it is lesser known than its more famous cousins. Golden beryl is also known as "precious beryl" and pale golden beryl stones are sometimes referred to as "heliodor", which comes from the Greek for "gift of the sun".
Brown Hessonite GarnetBack to Top
Hessonite is a honey-yellow, orange or reddish-brown grossular garnet variety that is also known as "cinnamon stone" or "kaneel stone" because of its brown-red color, which comes from traces of manganese. Hessonite garnet is an important Vedic astrology stone and also a January birthstone. Typically a heavily-included stone, hessonite is generally transparent to translucent with a vitreous luster. Hessonite has a remarkably high refractive index, giving it exceptional brilliance. It is found in various locations, but the most famous source for hessonite garnet is Sri Lanka.
Brown JasperBack to Top
Jasper is a type of opaque chalcedony that is assigned its own gem group because it has a grainy structure that differs from typical chalcedony. The name "jasper" comes from the Greek for "spotted stone" with reference to its multicolored spots, stripes and other patterns. The variegated appearance of jasper is owed to the fact that it is composed of up to twenty percent foreign materials. This means that each jasper gemstone is quite unique and there is an almost infinite variety of colors and patterns. Trade names for jasper incude "Zebra jasper"; which refers to dark-brown jasper with zebra-like bands.
Brown KornerupineBack to Top
Kornerupine is a rare magnesium aluminum borosilicate gemstone named after Danish naturalist, artist and explorer, Nikolaus Korneup. Despite being known since 1887, kornerupine remains a lesser-known gemstone. Kornerupine gems may be brown, brownish-green, green, white, pink, yellow or blue and are also sometimes traded as "prismatine", in reference to their long, prismatic crystal structure. Pronounced pleochroism is an interesting property of kornerupine, which can display yellow, green and brown in a single gemstone, depending on the viewing angle.
Brown Mali GarnetBack to Top
Mali garnet is a rare "hybrid" grossular garnet variety from Mali in West Africa that was discovered in 1994, making it a relatively recent addition to the garnet gemstone group. The colors of Mali garnet range from yellow to brown, with the most valued stones being green. Its remarkable dispersion and high refractive index give Mali garnet wonderful fire and brilliance, which is showcased by facet cuts. Mali garnet gems are transparent to opaque and have a Mohs hardness of 7.
Brown MoonstoneBack to Top
Moonstone is an orthoclase potassium feldspar gemstone that exhibits adularescence; an undulating glow that is a result of light interference and is sometimes called "sheen". Moonstone gems are transparent to translucent and occur in many colors, including white, yellow, orange and brown; these brown gems are often referred to as "mocha moonstone". Asterism (the star effect) can also occur in moonstone gems and these star moonstones have four-rayed stars as well as adularescence. Even rarer is cat's eye moonstone.
Brown ObsidianBack to Top
Obsidian is natural volcanic glass that forms as lava cools and can take various forms and colors, depending on the composition of the lava. For example, "mahogany obsidian" has reddish-brown streaks running through it and "gold sheen", as the name suggests, has a golden, glittery sheen. In its pure form, obsidian has a dark body color, due to the presence of iron and magnesium. Obsidian is transparent to opaque with a vitreous luster and has been used as a gemstone for many years. Obsidian gemstones are often made into cabochons, carvings or cut into spheres.
Brown Opal in MatrixBack to Top
Opal in matrix is a "type 3" opal that occurs when precious opal is randomly dispersed in tiny fragments throughout the host rock, unlike boulder opal, which has seams of precious opal. The play of color in opal in matrix appears as pins or dots of colors that contrast beautifully against its dark-brown to black body color. Opal in matrix gemstones can be found in Honduras and are also therefore traded as "Honduran black opal". Opal in matrix gemstones are generally cut as cabochons.
Brown PietersiteBack to Top
Pietersite is a rare dark-gray, midnight-blue, reddish or brown aggregate that is composed of mostly hawk's eye and tiger's eye (crocodilite). The crocodilite of pietersite appears as chatoyant (light-reflecting) swirls or streaks. When pietersite has more tiger's eye content, it results in a brown pietersite gemstone. To showcase their chatoyancy, pietersite gemstones are cut as cabochons.
Brown QuartzBack to Top
Quartz gemstones that do not quite fit the golden yellow definition of citrine or the darker, less reddish color of smoky quartz are sometimes sold as "whiskey quartz" or "beer quartz". Such brown quartz gemstones are pale-brown to rich reddish-brown and may be heat-treated. This is a stable and permanent color enhancement that is disclosed by all good gemstone dealers. Brown quartz stones are transparent to opaque and have a Mohs hardness of 7.
Brown Rutile QuartzBack to Top
Rutile quartz is transparent quartz that contains rutile (titanium dioxide) inclusions in the form of needles, which may be black, green, red or brown and make an internal landscape inside the gem. When the rutile inclusions are dense, the color of the gemstone appears to take on the color of the inclusions. Thus, rutile quartz stones that contain dense, brown rutile inclusions look brown. These intriguing but affordable gemstones are cut in many different shapes and styles.
Brown SapphireBack to Top
Sapphire is corundum that occurs in almost every color except for red; red corundum is known as ruby. Brown sapphire varies from light, golden brown to rich, dark-brown and many colors in between. It is not the most sought-after sapphire color, but brown sapphire has gained popularity in recent years, as a more affordable alternative to champagne and cognac diamonds. The second-hardest material on earth, sapphire is transparent to opaque with great brilliance and a vitreous luster.
Brown ScapoliteBack to Top
Scapolite is a rare gemstone that is mostly seen in gem and mineral collections. Scapolite gemstones occur in various colors, including yellow, violet, orange, pink, gray, colorless and brown. There are several varieties of scapolite, such as rainbow scapolite, which is colorless scapolite with multicolored inclusions and cat's eye scapolite, which has parallel-aligned inclusions causing light to be reflected in the shape of the slit eye of a cat. Cat's eye scapolite has nice, sharp cat's eyes and is often a rich brown color.
Brown SillimaniteBack to Top
Sillimanite is made of the same polymorphic material as both andalusite and kyanite; aluminum silicate. Though these three gemstones share the same composition, their crystal structures differ. Transparent sillimanite is rarely found, but is typically greenish to yellow in color, with the occasional light-blue or violet-brown stone. Cat's eye sillimanite is usually brown, though it can also be violet. Sillimanite is the official state mineral of Delaware, though it was originally found in Connecticut.
Brown Smoky QuartzBack to Top
Smoky quartz is a brown, smoky-gray or black quartz gemstone that occurs when colorless rock crystal is exposed to natural radiation in the earth. Smoky quartz has gained popularity since the trend for cognac diamonds, but unlike brown diamonds, smoky quartz gemstones are affordable, even in large sizes. Unscrupulous gemstone dealers sometimes sell smoky quartz gemstones as "smoky topaz", which does not exist. Smoky quartz can be found in almost every shape and cut imaginable, making it extremely versatile.
Brown Spessartite GarnetBack to Top
Spessartite is one of the many garnet varieties that gets its name from "Spessart", which means "forest" and is a mountain range in Germany where spessartite was discovered in the 1800s. Spessartite garnet gets its color from manganese and may range from yellowish-orange "mandarin spessartite" to red-brown. It is prized for its fiery color and high level of brilliance. Spessartite garnet gemstones were rarely seen until deposits were found in Mozambique and Namibia in the 1990s. Eye-clean spessartite garnet gemstones are quite rare, with most being included.
Brown SphaleriteBack to Top
Sphalerite is composed of zinc ore and has very high dispersion, giving it incredible "fire", as well as fiery yellow, orange, red and brown colors. Its resinous to adamantine luster also adds to sphalerite's attraction. Since sphalerite lacks hardness, it is mainly a collector's stone. Sphalerite is found in several locations, including Bulgaria, Canada, Spain, the Congo, Namibia, the USA and Zaire, however, it is rarely found in gemstone quality.
Brown Tiger's EyeBack to Top
Tiger's eye is a golden brown, opaque variety of fibrous quartz that is valued for its chatoyancy (the cat's eye effect). This optical phenomenon is caused by parallel inclusions that reflect rays of light. In order to best display this, tiger's eye gemstones are often given a cabochon cut. Tiger's eye is related to hawk's eye and pietersite, and is commercially mined in several areas of the world, though currently, the most important tiger's eye deposits are South Africa and Thailand.
Brown Tiger's Eye MatrixBack to Top
Tiger's eye matrix is tiger's eye which is cut and finished with some of the matrix (host rock) intact. When tiger's eye, red jasper and black hematite are all present, it is traded as "tiger's iron". Depending on composition, tiger's eye matrix gemstones can show the whole range of golden tiger's eye, gray to black hematite and red jasper colors, in swirls or bold bands. Since tiger's eye matrix is an aggregate, its luster varies according to its content; hematite has a metallic luster, tiger's eye has a changeable luster and jasper has a dull to vitreous luster.
Brown TopazBack to Top
Topaz is an aluminum silicate gemstone that is colorless in its pure form and various other colors, including golden brown, when it contains trace impurities. Brown topaz gemstones are translucent to transparent with a vitreous luster and a Mohs hardness of 8. Less valuable smoky quartz gemstones are sometimes misleadingly sold as "smoky topaz". Trade names for golden and brown topaz gems include "sherry topaz" and "precious topaz". Some of the largest brown topaz crystals in the world have been mined from Brazil and Ukraine.
Brown TourmalineBack to Top
Tourmaline is a boron silicate mineral that occurs in every color of the rainbow, including brown. One of the fascinating phenomena of brown tourmaline gemstones is their pleochroism; the ability to exhibit different colors depending on the viewing angle. This results in interesting multicolor tourmaline gemstones that may be brown, yellow and green all in one stone. Brown tourmaline has a Mohs hardness of 7-7.5 and a vitreous luster. Trade names for brown tourmaline include "dravite" and "tsilaisite".
Brown ZirconBack to Top
Zircon is one of the oldest minerals on earth and also a brilliant gemstone that is often used as a diamond substitute. It is often confused for the synthetic material; cubic zirconia, but zircon is zirconium silicate and is mined from the earth. Zircon gemstones are transparent to translucent with remarkable fire and brilliance. They also have a high level of birefringence, sometimes resulting a fuzzy appearance. Zircon gems occur in many colors, including colorless, yellow, orange, red, pink, violet, blue, green and brown.
- First Published: August-01-2017
- Last Updated: August-15-2017
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