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What is Citrine?

Citrine Pendant

Citrine is the yellow to red-orange variety of crystalline quartz. Clever marketing and the rise of “earth tone” fashions have made this durable and readily available gem a popular jewelry stone in recent years.

Citrine Stone [2]

In terms of color, at the top end of the scale, you’ll find prime specimens of the most saturated yellow, orange, and reddish tones. Those with less intense color fall into lower value ranges, with pale or smoky stones at the bottom.

There’s no exponential increase in value per carat with increase in size, as larger sizes are readily available. Inclusions will decrease value.

As with any gem material, custom cutting increases value. In many fancy cut or carved specimens, most of the value is due to the artistry of the cutting.

Citrine was once the Rodney Dangerfield of the gem world. Due to its abundance, it would “get no respect,” as it were. In recent decades, this perception has changed, partly because earth-tone jewelry has come into vogue. Home shopping networks have also marketed the various shades of citrine aggressively, with catchy adjectives like “butterscotch” and “whiskey.” Apparently, this has worked. Citrine is now a modern alternative birthstone for November.

Mining actually yields very little citrine. The vast majority of citrine on the market is produced by heating smoky quartz (which produces light to medium yellows) and amethyst (which produces stronger yellows and orange-red to orangey brown shades). Natural stones usually occur in pale yellow colors, often with smoky tones.

Citrine Earring [2}

Citrine as a Jewelry Stone

Citrines make fine jewelry stones. With no cleavage and a hardness of 7, they can be used for any jewelry application. Like most quartz, it’s available in large sizes. Thus, custom gem cutters can easily use this stone for dramatic and intricate cuts.

Citrine’s yellow colors are due to the presence of ferric iron, colors traditionally associated with topaz. Confusion between these gemstones does occur, even though quartz and topaz are distinct gem species.

Misnomers

In the past, people commonly referred to citrine by misleading names, such as “Brazilian topaz,” “Madeira topaz,” and even “topaz quartz.” Unscrupulous vendors can still take advantage of the long association of yellow with topaz to pass off inexpensive citrines as more expensive topaz pieces. For more examples, consult our list of misleading or false gemstone names.

Care

Citrines make durable jewelry stones that require little special care. However, heat-treated stones may fade when exposed to heat. Thus, avoid steam cleaning or boiling your citrine jewelry. Instead, use either ultrasonic cleaning or simply warm water, mild detergent, and a soft brush.

Although usually free of inclusions, citrines with low clarity grades — with liquids, gases, or crystals trapped within them — should be cleaned by hand only. However, any heat-treated citrines are most likely safe to clean in an ultrasonic cleaner. [1]

Sources

[1} International Gem Society
[2] Freepik

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What is Aquamarine?

Aquamarine stone

What is Aquamarine? Named after the color of sea water, aquamarine is the blue to blue-green member of the beryl family. Readily available and moderately priced, the modern March birthstone makes an excellent jewelry stone.

White Blue Chocolate Candy Aquamarine [2]

What is the Color of Aquamarine?

This beautiful gem receives its coloring from trace amounts of ferrous iron. Its hues range can range from blueish green, blue-green, greenish blue, to deep blue, and its tones can vary from very light to moderately dark. You’ll rarely see aquamarines darker than a Swiss blue topaz. When you do, the color is usually enhanced by the cut.

You might encounter gemstones sold as “white aquamarines.” Be aware that such stones are most likely colorless beryls, also known as goshenites.

What Does Aquamarine Symbolize?

In Western cultures, due to aquamarine’s color and name, this gem has a folklore strongly connected to the sea. Its mystical purview traditionally includes protection for sailors and fishermen as well as travelers in general.

What Inclusions do Aquamarines Contain?

Inclusions are interesting features of this gemstone. Beryl, and aquamarine in particular, are known for having long, hollow tubes. This distinctive feature can help identify a gem as a member of the beryl family.

Aquamarines may have transparent and metallic inclusions, such as biotite, hematite, ilmenite, phlogopite, pyrite, and  rutile in skeletal crystals. They may also contain crystals of apatite, cassiterite, epidote, garnet, muscovite; quartz, and tourmaline. Some stones contain “snow-stars,” irregularly shaped liquid droplets in a star formation. The Martha Rocha aquamarine has notable “snow-star” inclusions.

[2]

Aquamarine Cat’s Eyes and Star Stones

With enough hollow tube inclusions and proper cutting, aquamarines can show chatoyancy and even asterism. Collectors prize beautiful cat’s eye aquamarines very highly, and their prices come very close to that of clean, faceted gems with the same coloring. Star aquamarines are even more rare than cat’s eyes and can command premium prices.

Are There Lab-Created Aquamarines?

Aquamarines can be synthesized, and an examination under a microscope may find some indications of synthetic origin. However, professional gem labs have advanced instruments that can distinguish natural from created aquamarines.

Are Aquamarine Gemstones Enhanced?

Most aquamarines come out of the ground with a greenish tint, but this will disappear after heating to 375° C, which leaves a pure blue color. Removing aquamarine’s green tinting through heat treatment is very common. In the past, this was done routinely. Nowadays, a more sophisticated public has started appreciating slightly green, untreated aquamarines. However, distinguishing this heating process proves impossible. Therefore, gem graders should describe any pure blue aquamarines as “probably heat treated.”

In the 1970s, Maxixe (pronounced mah-SHE-she), a very dark blue aquamarine, appeared on the market, but the color of this irradiated product wasn’t stable. Although these stones have mostly disappeared from the market, if you’re ever offered a very deep blue aquamarine, buyer beware.

You can distinguish the Maxixe from a natural aquamarine by its lack of pleochroism. Natural aquamarines have distinct blue and colorless dichroism. On the other hand, the Maxixe has no pleochroism. When viewed from any angle, it just shows blue. The absorption spectrum of natural aquamarine and the Maxixe also differs. With a spectroscope, you’ll see a narrow line at 6950, a strong line at 6540, and weak lines at 6280, 6150, 5500, and 5810. This differs considerably from natural aquamarine’s spectrum, with a broad band at 4270 and a diffuse band at 4560.

You can also distinguish a Maxixe aquamarine from a natural stone with a dichroscope. Both windows remain blue when viewing a Maxixe. In contrast, one window should be colorless or pale yellowish when viewing an untreated specimen.

Where are Aquamarine Gemstones Found?

  • Brazil is the world’s major source of fine aquamarine gems. Localities include Minas Gerais, Rio Grande do Norte, Ceara, and others.
  • Madagascar has more than 50 specific localities that produce fine, blue gem material.
  • Other notable sources include the following:
  • United States: San Diego County, California (not much gem material); Mt. Antero, Colorado; Connecticut (some gem); Maine; North Carolina.

Aquamarine Trade Names

  • Brazilian aquamarine: blueish green. Also a misnomer for blueish green topaz.
  • Madagascar aquamarine: fine, medium blue.
  • Maxixe beryl: treated beryl with excellent aquamarine blue, known for fading. Also called halbanite.
  • Santa Maria aquamarine: medium-dark tone and highly saturated blue color.
  • Don’t assume aquamarines billed as “Brazilian” or “Madagascar” actually come from these sources. These terms may only refer to the color, so ask to see documentation to certify a gem’s origin. “Santa Maria” aquamarines are named after the Santa Maria de Itabira mine where they were first discovered, but stones with similar colors have also been found in other locations.

In My Shop

Sources

[1] International Gem Society
[2] Photos by Freepik

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What is Howlite?

howlite beads

Howlite was discovered near Windsor, Nova Scotia, in 1868 by Henry How (1828–1879), a Canadian chemist, geologist, and mineralogist. How was alerted to the unknown mineral by miners in a gypsum quarry, who found it to be a nuisance. He called the new mineral silico-boro-calcite; it was given the name howlite by the American geologist James Dwight Dana shortly thereafter.

Howlite Stone
[2]

Howlite is commonly used to make decorative objects such as small carvings or jewelry components. Because of its porous texture, howlite can be easily dyed to imitate other minerals, especially turquoise because of the superficial similarity of the veining patterns. Howlite is also sold in its natural state, sometimes under the trade names of “white turquoise” or “white buffalo turquoise,” or the derived name “white buffalo stone” and is used to produce jewelry similar to how turquoise is used. Varieties of the unrelated gemstone turquoise which are white instead of the typical blue or green color have been mined in the US States of Arizona and Nevada, and are also marketed as “white buffalo turquoise”. Most of the white varieties of turquoise are chalk-like with a Mohs hardness of 1, and are not as hard or durable as howlite, and subsequently require stabilization in order to be used in jewelry, which has resulted in howlite being more popular for use in jewelry than the artificially stabilized white forms of the mineral turquoise. [1]

Howlite is always opaque in nodules; it is an abundant material and easy to acquire. Sometimes it contains black, threadlike impurities resembling the veining in turquoise. Howlite is frequently dyed blue to resemble turquoise, and it makes a most convincing simulant. The white material is relatively unexciting in appearance. [3]

In My Shop

Sources

[1] Wikipedia
[2] Photo by Freepik
[3] International Gem Society

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What is Jasper?

Jasper Stone

Jasper is an opaque, solid or patterned variety of cryptocrystalline quartz which consists of very tiny quartz crystals colored by various mineral impurities. The names of various jaspers can come from their color: bloodstone, green, lemon; from their pattern: orbicular, poppy, leopardskin, landscape, Picasso; or from a place name: Morrisonite, Mookite. All types take an excellent polish, are trouble free to care for, and hardy enough for all jewelry uses. These stones are usually cabbed, sometimes carved, and seldom faceted. Jewelry use of jaspers goes back into the early history of civilization. Various forms of this material are also frequently made into decorative objects, such as ashtrays or bookends. Jaspers are found all over the world, with certain colors or patterns unique to particular locales. Most bloodstone comes from India, all Mookaite from Australia. [1]

Jaspers, in general, are very common; hence most of the value in a given piece relates to the saturation of its color, the beauty of its pattern or the artistry with which it is fashioned. Some types such as Imperial Jasper and Madagascar Jasper do command premium prices since they are relatively rare. In rock shops, pieces of commercial quality cut in simple shapes might be had for $5 or less. Fine material, cut in designer forms, generally ranges between $2 and $5 per carat. [1]

In Our Shop

Sources

[1] International Gem Society
[2} Images by freepik

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What is Rhodochrosite?

Rhodochrosite

Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO3. In its pure form (rare), it is typically a rose-red colour, but it can also be shades of pink to pale brown. It streaks white, and its Mohs hardness varies between 3.5 and 4.5. Its specific gravity is between 3.45 and 3.6. The crystal system of rhodochrosite is trigonal, with a structure and cleavage in the carbonate rhombohedral system. The carbonate ions (CO2−3) are arranged in a triangular planar configuration, and the manganese ions (Mn2+) are surrounded by six oxygen ions in an octahedral arrangement. The MnO6 octahedra and CO3 triangles are linked together to form a three-dimensional structure. Crystal twinning is often present. It can be confused with the manganese silicate rhodonite, but is distinctly softer. Rhodochrosite is formed by the oxidation of manganese ore, and is found in South Africa, China, and the Americas. It is one of the national symbols of Argentina and the state of Colorado.

Rhodochrosite forms a complete solid solution series with iron carbonate (siderite). Calcium (as well as magnesium and zinc, to a limited extent) frequently substitutes for manganese in the structure, leading to lighter shades of red and pink, depending on the degree of substitution. This is the reason for the rose color of rhodochrosite. [1}

Many people also wear rhodochrosite crystal jewelry or carry a small piece with them throughout the day to benefit from its healing and grounding properties. No matter how you choose to incorporate rhodochrosite into your life, this crystal is sure to enhance your well-being and spiritual journey.

Argentine Rhodochrosite Earrings

$27.00

These Argentine Rhodochrosite Earrings are composed of Pink Argentine Rhodochrosite Beads, gold plated spacer beads and earring components

2 in stock

[1} Wikipedia
FreePix

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What is Kyanite?

Kyanite

Kyanite is a typically blue aluminosilicate mineral, found in aluminium-rich metamorphic pegmatites and sedimentary rock. It is the high pressure polymorph of andalusite and sillimanite, and the presence of kyanite in metamorphic rocks generally indicates metamorphism deep in the Earth’s crust. Kyanite is also known as disthene or cyanite.

Kyanite is strongly anisotropic, in that its hardness varies depending on its crystallographic direction. In kyanite, this anisotropism can be considered an identifying characteristic, along with its characteristic blue color. Its name comes from the same origin as that of the color cyan, being derived from the Ancient Greek word κύανος. This is typically rendered into English as kyanos or kuanos and means “dark blue.”

kyanite stone

Kyanite is used as a raw material in the manufacture of ceramics and abrasives, and it is an important index mineral used by geologists to trace metamorphic zones. [1]

Since most kyanites are heavily included, don’t clean these gems with mechanical cleaning systems, like steam and ultrasound. Clean them only with a soft brush, mild detergent, and warm water. [2]

[1] Wikipedia
FreePix
[2} International Gem Society

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What is Jade?

Jade

Jade is an umbrella term for two different types of decorative rocks used for jewelry or ornaments. Jade is often referred to by either of two different silicate mineral names: nephrite (a silicate of calcium and magnesium in the amphibole group of minerals), or jadeite (a silicate of sodium and aluminum in the pyroxene group of minerals). Nephrite is typically green, although may be yellow, white or black. Jadeite varies from white or near-colorless, through various shades of green (including an emerald green, termed ‘imperial’), to lavender, yellow, orange, brown and black. Rarely it may be blue. Both of these names refer to their use as gemstones, and each has a mineralogically more specific name. Both the amphibole jade (nephrite) and pyroxene jade are mineral aggregates (rocks) rather than mineral species. Nephrite was deprecated by the International Mineralogical Association as a mineral species name in 1978 (replaced by tremolite). The name “nephrite” is mineralogically correct for referring to the rock. Jadeite, is a legitimate mineral species, differing from the pyroxene jade rock. In China, the name jadeite has been replaced with fei cui, the traditional Chinese name for this gem that was in use long before Damour created the name in 1863.

raw jade

Jade is well known for its ornamental use in East Asian, South Asian, and Southeast Asian art. It is commonly used in Latin America, such as Mexico and Guatemala. The use of jade in Mesoamerica for symbolic and ideological ritual was influenced by its rarity and value among pre-Columbian Mesoamerican cultures, such as the Olmecs, the Maya, and other ancient civilizations of the Valley of Mexico.

Jade is classified into three main types: Type A, Type B, and Type C. Type A jade refers to natural, untreated jadeite jade, prized for its purity and vibrant colors. It is the most valuable and sought-after type, often characterized by its vivid green hues and high translucency. Type A jade is revered for its symbolism of purity, harmony, and protection in various cultures, especially in East Asia where it holds significant cultural and spiritual importance. Types B and C have been enhanced with resin and colourant respectively.

Wikipedia
International Gem Society

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What is Tourmaline?

tourmaline gems

Tourmaline is a name applied to a family of related minerals with widely varying properties. Tourmalines make very popular jewelry stones and comes in an amazing range of colors, like pink, blue, green, yellow, colorless, and black. Stones can also include multi-color zones.

Ready availability keeps tourmaline prices reasonable. Small tourmalines (under 5 carats) are fairly easy to obtain at modest cost. Only when you get into large sizes or extremely rare or fine colors do prices go over a few hundred dollars per carat.

Most colors are fairly common, but pure blue, red, orange, yellow, and purple stones are rare. Such stones usually command higher prices. Color-change tourmalines are also exceptionally rare. Neon-blue paraíba tourmalines, raspberry-red rubellites, and emerald-green chrome tourmalines are especially prized.

Brightly colored Ceylonese gem tourmalines were brought to Europe in great quantities by the Dutch East India Company to satisfy a demand for curiosities and gems. Tourmaline was sometimes called the “Ceylonese Magnet” because it could attract and then repel hot ashes due to its pyroelectric properties.

Tourmalines were used by chemists in the 19th century to polarize light by shining rays onto a cut and polished surface of the gem. 


The most common species of tourmaline is schorl, the sodium iron (divalent) endmember of the group. It may account for 95% or more of all tourmaline in nature. The early history of the mineral schorl shows that the name “schorl” was in use prior to 1400 because a village known today as Zschorlau (in Saxony, Germany) was then named “Schorl” (or minor variants of this name), and the village had a nearby tin mine where, in addition to cassiterite, black tourmaline was found. The first description of schorl with the name “schürl” and its occurrence (various tin mines in the Ore Mountains) was written by Johannes Mathesius (1504–1565) in 1562 under the title “Sarepta oder Bergpostill”. Up to about 1600, additional names used in the German language were “Schurel”, “Schörle”, and “Schurl”. Beginning in the 18th century, the name Schörl was mainly used in the German-speaking area. In English, the names shorl and shirl were used in the 18th century. In the 19th century the names common schorl, schörl, schorl and iron tourmaline were the English words used for this mineral.


Dravite

Dravite, also called brown tourmaline, is the sodium magnesium rich tourmaline endmember. Uvite, in comparison, is a calcium magnesium tourmaline. Dravite forms multiple series, with other tourmaline members, including schorl and elbaite.

The name dravite was used for the first time by Gustav Tschermak (1836–1927), Professor of Mineralogy and Petrography at the University of Vienna, in his book Lehrbuch der Mineralogie (published in 1884) for magnesium-rich (and sodium-rich) tourmaline from village Dobrova near Unterdrauburg in the Drava river area, Carinthia, Austro-Hungarian Empire. Today this tourmaline locality (type locality for dravite) at Dobrova (near Dravograd), is a part of the Republic of Slovenia. Tschermak gave this tourmaline the name dravite, for the Drava river area, which is the district along the Drava River (in German: Drau, in Latin: Drave) in Austria and Slovenia. 

Dravite varieties include the deep green chromium dravite and the vanadium dravite.


A lithium-tourmaline elbaite was one of three pegmatitic minerals from Utö, Sweden, in which the new alkali element lithium (Li) was determined in 1818 by Johan August Arfwedson for the first time. Elba Island, Italy, was one of the first localities where colored and colorless Li-tourmalines were extensively chemically analysed. In 1850, Karl Friedrich August Rammelsberg described fluorine (F) in tourmaline for the first time. In 1870, he proved that all varieties of tourmaline contain chemically bound water.


Tourmaline has a variety of colors. Iron-rich tourmalines are usually black to bluish-black to deep brown, while magnesium-rich varieties are brown to yellow, and lithium-rich tourmalines are almost any color: blue, green, red, yellow, pink, etc. Rarely, it is colorless. Bi-colored and multicolored crystals are common, reflecting variations of fluid chemistry during crystallization. Crystals may be green at one end and pink at the other, or green on the outside and pink inside; this type is called watermelon tourmaline and is prized in jewelry. An excellent example of watermelon tourmaline jewelry is a brooch piece (1969, gold, watermelon tourmaline, diamonds) by Andrew Grima (British, b. Italy, 1921–2007), in the collection of Kimberly Klosterman and on display at the Cincinnati Art Museum. Some forms of tourmaline are dichroic; they change color when viewed from different directions.

The pink color of tourmalines from many localities is the result of prolonged natural irradiation. During their growth, these tourmaline crystals incorporated Mn2+ and were initially very pale. Due to natural gamma ray exposure from radioactive decay of 40K in their granitic environment, gradual formation of Mn3+ ions occurs, which is responsible for the deepening of the pink to red color.

International Gem Society
Wikipedia