Topaz – How to Identify

by Ardamun

Citrine is mostly, and erroneously, called topaz, though both are two distinct species. Citrine is quartz, and is much lighter than topaz, which is Hydroxyl Fluorosilicate of Aluminum.

How To Identify Different Topaz?

Topaz is the hardest silicate mineral and one of the hardest minerals in nature, and a very popular gemstone for jewelry. In the ancient past, topaz was always associated with the yellow color, and all yellow and golden-hued gems were called topaz. Fine topaz normally occurs as a colorless crystal, though other colors, such as pink, blue, green, ‘sherry’, brown, etc are known to occur as well. You will find a variety of yellow gems wrongly being sold as topaz, such as:

• Smoky topaz – which is actually smoky quartz
• Citrine topaz – which is citrine
• Madeira topaz – a citrine quartz
• Bohemian topaz – which is also citrine
• Occidental topaz – is also citrine
• Oriental topaz – which is yellow corundum

image courtesy: theimage.com

Citrine is mostly, and erroneously, called topaz, though both are two distinct species. Citrine is quartz, and is much lighter than topaz, which is Hydroxyl Fluorosilicate of Aluminum. Quartz has a Specific Gravity of 2.65 and the Refractive Index of 1.540 to 1.550, whereas topaz has a Specific Gravity of 3,54 and a higher Refractive Index of 1.620 to 1.630.

True topaz is correctly labeled and some are preceded by two words – Precious or Imperial. Natural color topaz is known as precious topaz and imperial topaz, whereas the Imperial Topaz was the topaz with pink tones which were discovered in the 19th century Russia. Imperial topaz is now mined at the Imperial Topaz Mines in Minas Gerais, Brazil.

Topaz is an aluminum fluorite silicate – Al2F2SiO4 – and is found in cavities in granite and rhyolite lava rocks, pegmatites, high temperature quartz veins, and as worn pebbles in alluvial deposits.

The Origin and Colors of Topaz

The name topaz is thought to come from the Sanskrit word – tapas – which means fire. In 1 A.D. it was thought that the name was derived from the Greek word topazos or topazion – meaning to seek – and which was the name of an island – Topazos Island – in the Red Sea. Today, this island is known as ‘Zeberget’, or the ‘Island of St. John’.

Clear or colorless topaz is quite common and has little value. Blue topaz, which is very rare in nature, can be made by irradiating clear topaz. Natural blue topaz is very light in color and irradiation produces blue topazes of darker hues. Treated blue topaz is available from very light, to sky-blue, to almost an inky dark blue. These flawless gemstones are relatively less expensive. The pale or clear topaz that is enhanced to produce blue topaz is mined in Brazil, Sri Lanka, Nigeria, and China. Blue topaz is often confused with aquamarine.

The mines in Utah and Mexico produce the reddish-brown topaz. Though not of high value, they are still more expensive than citrine. Pink topaz is quite rare and hence is highly valued and occasionally found in jewelry. It is found in Pakistan and Russia. Pink topaz is also created by irradiating the common yellow topaz.

Another topaz that is rare is the green topaz, and is highly valued also. The most prized is the Imperial Topaz, which ranges from red-orange to pink-orange color. This topaz normally contains many flaws and is very heat sensitive. Presently, it is mined in small quantities in Brazil.

The other colors of topaz are yellow, brown, orange, beige, and red.

The Deceptive Names of Topaz

Certain unscrupulous jewelers sell other gemstones, with deceptive names, as topaz. The names, such as gold topaz, Madeira topaz, Brazilian topaz, Bahia topaz, citrine topaz, Indian topaz, and smoky topaz are not the names of topaz. These are just names to deceive you into thinking they are topazes.Citrine is also sold as topaz under the names – Bohemian topaz, Madeira topaz, Colorado topaz, Quartz topaz Saxon topaz, Jeweler’s topaz, Scotch topaz, Palmyra topaz, Salamanca topaz, and Occidental topaz. Few more trade names are Hyacinth topaz, Nevada topaz, and Hawaiian golden yellow topaz.

A variety of quartz are also enhanced and sold as topaz. They go under the name – Palmeira Topaz, Madeira Topaz, Gold(en) topaz, Rio Topaz, Hinjosa topaz, Smoky Topaz, Spanish topaz, Scottish topaz, Topaz quartz Orange topaz, and Topaz saffronite. Poor quality sapphire is also enhanced and sold as topaz. They go by the names – as Indian topaz, Palmeira topaz, Star topaz, King topaz, and Topaz cat’s eye.

Enhancement of Colorless Topaz

Topaz is found on most of the continents, with the colorless variety being the most common. Due to its availability in abundance, it has a very little value. The colorless topaz is enhanced either by radiation and/or by heating. The natural blue topaz is of a very pale blue color. Today, a mass production of a desirable and darker blue color is done through electron beam enhancement or radiation of colorless topaz. The most common blue topazes produced by radiation are:

Sky Blue Topaz – which is a moderately strong light blue topaz resulting from treating colorless topaz with gamma rays from Cobalt 60 or electrons by electron accelerators. The treatment is then followed by heat treatment.

London Blue Topaz – this slightly grayish medium dark to dark blue topaz results from treating colorless topaz with neutrons produced in nuclear reactors. This process is also followed by heat treatment.

Swiss Blue Topaz – is a vivid medium, to medium dark blue topaz produced by combining neutron treatment with electron treatment, followed by heat treatment.

After the electron beam treatment, the heat treatment is carried out at 200ºC for many hours. This achieves strong blue colors. After neutron irradiation, topaz needs a cool off time as it becomes radioactive.

The common yellow topaz, when irradiated converts to pink topaz. Typically, yellow topaz ranges from wine to straw-colored, and heat-treated yellow topaz turns reddish-pink. Heating is one of the most common treatments for topaz. The process can cause the gemstone to change completely, or either lighten or darken. Normally the heat treatment is irreversible. Heat-treated topazes are widely available in blues and pinks.

Topaz is not a very expensive gemstone, and with a variety of colors and sizes available can be an exquisite addition to your wardrobe.

Topaz Mines

by Ardamun

The state of Minas Gerais in Brazil is famous as it produces 80% of Brazil’s gems and minerals. The most important of all is topaz, which is mined around Ouro Prêto in Minas Gerais. Most of the precious topaz and all of the pink topaz mined in Brazil is mined from an area less than 100 square miles around Ouro Prêto.

Topaz Mines

Topaz has been used for centuries in jewelry. Pure topaz is colorless, but the presence of various impurities impart it with various colors, such as yellow, brown, orange, beige, red and green. The color of topaz is relative to the proportion of water or fluorine in it. More the water content in the crystals, more yellow to brown the color; and more the fluorine content, more bluish or colorless the mineral. The most popular is its fiery orange yellow color.

The origin of the name topaz is supposed to be the Sanskrit word for fire – tapas – possibly because of its fiery orange yellow color. According to another theory, it got it name from the Red Sea’s Island of Topazos, where the Romans found a stone, which they called ‘Topaz’, but which later was found to be Peridot.

Exposure to heat or sunlight is known to cause it to change its color. Sunlight is known to bleach brown topaz, and yellow topaz turns to pink or purplish red on exposure to heat. Blue topaz is artificially created after being irradiated. Though it is assumed that all blue topaz is treated topaz, blue topaz has been found to occur naturally in Texas, and in the Ural Mountains in Russia. A brilliantly cut colorless topaz is often mistaken for a diamond. Topaz is known to occur in Minas Gerais, Brazil; Pakistan; San Diego, California; the Ural Mountains, Russia; Mexico; and the Thomas Range, Utah.

Topaz Mines in Minas Gerais, Brazil

The state of Minas Gerais in Brazil is famous as it produces 80% of Brazil’s gems and minerals. The most important of all is topaz, which is mined around Ouro Prêto in Minas Gerais. Most of the precious topaz and all of the pink topaz mined in Brazil is mined from an area less than 100 square miles around Ouro Prêto. The Antonio Pereira Mine is where the Imperial Topaz is mined. The Imperial Topaz is the red and pink topaz – so called because they were used in the jewelry of the 18th and 19th Century Russian Czarinas.

The imperial topaz mines are largely open air mines, and are said to be the last imperial topaz mines in the world, after the closure of the last Russian mines. The production of topaz at Minas Gerais is very less, but their prices have gone up tremendously since the closure of the Russian mines.

Topaz Mines in Pakistan

Pakistan is rich in a variety of minerals, and in the case of topaz, produces various colors, such as violet and pink, golden and champagne. In addition to other minerals, topaz in Pakistan is mined in the:

* Gilgit district – Gilgi , Hunza, and Shigar
* Baltistan Skardu Road, Baltistan district – Shengus, Stak Nala, and Tormiq Nala
* Shigar area near Skardu in Baltistan district – Childee, Kashmal, and Yuno
* Katlang in Mardan district, among others.

Pakistan does not produce the natural orange topaz, and the topaz coming out of the Gilgit area – which is generally golden and white – is treated to impart this color. The well-formed spectacular peachy pink and white topaz crystals are glassy clean.

Topaz Mines in the Ural Mountains, Russia

The Ural Mountains – from Karski Sea to the Pre-Caspian steppes – stretch out for more than two thousand kilometers! Since the 5th century AD, from the times of Herodotus, the Urals have been known to be a rich source of crystals and precious stones, but it gained renown in the 17th century when many rich deposits of minerals and precious stones, including topaz, was discovered.

The topaz found in Russia is comparatively much smaller than most of the topaz from other sources. The popularity, though, is due to its natural deep blue color.

The Blyumovskaya mine, which is also known as 50 Kop or 50 mine, is a rich source of topaz. So is the river Kamenka, located near Koshkar, a known deposit for topaz. Though not of a high quality, the Sanarka River is also a deposit for topaz.

Topaz Mines in Mexico

Mineral wealth of Mexico has played a big role in its recorded history. At one time, the most precious and expensive topaz in North America was mined from the famous topaz mine – the renowned Guererro Mine in Mexico. Small quantities of the extremely rare bright pinkish gold color topaz is known to have been mined here. This mine has been closed down for the last 50 years or so.

Topaz is also found in the state of San Luis Potosí, in Mexico. It is found in the cavities in rhyolitic volcanic rocks. Topaz found here is very pale pink to colorless, or sherry brown. Deeply colored stones found here are known to fade in sunlight.

The Sierra Gorda hills are rich in a number of minerals, including topaz. The mines in Querétaro are famous for the world-class opal, but topaz is also mined here.

Topaz Mines in Myanmar (Burma)

Myanmar is well known for producing nine different kinds of gems, and topaz is one of them. Extraordinary topaz specimens are found in Pantaw, in the Mogok valley of Mandalay, in Myanmar. Mogok has been blessed with a number of minerals, especially the world famous Rubies of Myanmar – formerly known as Burma. Topaz from the mines in Mogok has excellent crystal clarity, and high class gem quality.

Fine specimens of topaz that can be cut into fine gemstones are found in the Sakangyi and Barnardmyo areas of Mogok. Large colorless topaz, natural blue, sherry, and pink specimens are mined in this region. The natural colored blue and brown topaz fade under sunlight.

Topaz Mines in America

Thomas Range, Utah – a paradise for mineralogists – is famous for its topaz, among other minerals. The Thomas Range topaz is popular for its sherry colored crystals. Crudely shaped white topaz is mined in Amelia, Virginia; clear topaz at Devils Head and Pikes Peak, Colorado; large and deeply etched blue crystals at Topsham, Maine; small topaz crystals – in small miarolitic cavities in granite – at Baldface Mountain, New Hampshire; and pale blue topaz crystals in Mason County, Texas.

Types of Topaz

by Ritika Changrani

The Topaz is a beautiful gem symbolizing love and affection. It can be found in a variety of colors ranging from red, pink to brown, blue and even colorless. A true topaz is known as an “imperial topaz”. The topaz is available in every imaginable shape and size, making it a coveted gem for jewelry settings.

The birthstone for those born in the month of November, the Topaz is the symbol of love and affection. A true Topaz is rare today. In fact, most people have never seen a topaz. What is available at most jewelry stores is just the quartz or citrine topaz, in other words, glass. In olden days, all yellow stones were called topaz. However, a topaz is available in a variety of brilliant hues and is extremely beautiful.

The topaz is a very hard stone, nearly as hard as the diamond. It has a wide color range and is very expensive. A true topaz will always be labeled as an “imperial topaz”. Be wary of name like “Spanish topaz”, ” Palmeira topaz”, “Bahia topaz”, “Citrine topaz” etc. as they are all names given to mislead customers – they are not topaz at all.

COLOR : The gem Topaz is commonly found to be either colorless or brown in color. The brown topaz may fade in color with time. The more popular varieties of topaz are rarer and occur in golden, pink, orange, purple and light to medium red. Most of the colors are as a result of combination of heat treatment and irradiation. The yellow and brown topaz appear so as a result of their color centers. If chromium, an impurity, is present, the gem will appear pink or red. Presence of chromium and color centers give rise to the orange topaz.

THE BLUE TOPAZ : The blue topaz is commonly found in nature as a result of color centers. It is a fine yet cheaper substitute to aquamarine in jewelry pieces. The types of blue colors that are present in a topaz are :

London Blue – It is the darkest blue. The lower quality crystals sometimes have a grey tone to it.
Electric Blue – This is the best color being very blue and vibrant and not as dark as the London Blue.
Sierra Blue – It is a medium blue, but not as deep or hot colored as the Electric Blue.
Swiss Blue – This is quite similar to Sierra Blue but a little lighter.
Sky Blue – It is a pale light blue in color.
Light Blue – This is pale, and very slight bluish tint.

CLARITY : A good quality topaz from any source will be reasonably clean. This is why eye – clean gems are possible and hence extremely desirable. The notable exceptions are red and pink topaz, which usually occur as small stones and thus, a higher degree of inclusions may be tolerated.

CUT : The topaz is typically cut as elongated gems because of their roughly elongated prisms. The common cuts used with the topaz are emerald cuts, cushions, elongated ovals and pears. The pears are often cut with overly narrow shoulders to save on weight. The blue topaz is mass produced due to the high demand and thus is cut in virtually all imaginable shapes and sizes. The topaz is rarely cabochon cut.

STONE SIZES : The stone topaz occurs in a variety of sizes and may even be enormous. Clean stones of 1000 cts. have known to be found. In fact, monster crystals have been cut to obtain faceted gems of tens of thousands of carats. The “imperial topaz” in orange, pink and red is rarer. Reds and pinks are typically found in 5 cts. or less. The orange topaz usually occurs in 20 cts. or less.

LIGHTING : In order to examine a topaz, correct lighting is essential. The orange, red, and orangish – red varieties are best looked at under incandescent light. On the other hand, the blue topaz generally looks best when seen in natural daylight or under fluorescent light. It is recommended to minutely study a gem under a variety of light sources before making the final purchase, to avoid any future shocks.

PRICES : The value of a topaz totally depends on its quality, like any other gem. To simplify things and to give you an idea, certain generalizations can be made. The most common and sought – after variety is the blue topaz. It is produced in large quantities in keeping with the demand. Because of its sheer availability the price of a blue topaz is usually $25 per carat for ring sizes, at a retail store. The larger sizes will obviously be slightly more expensive. The blue topaz occurs naturally, but owing to the mass production of treated blue topaz, the price of the natural blue has dropped down to that of its treated counterpart.

The brown topaz is available for $8 per carat. The colorless topaz, from which the blue topaz is produced through heat treatment and irradiation, sells for less than $8 per carat and is usually available in sizes upto 100 carats.

In stark contrast, the “imperial topaz” i.e. the rich orange or golden in color, sells for more than $1000 per carat for the larger sizes (more than 10 ct pieces). The most valuable and hence expensive is the rich pink or red topaz and can be bought for as high as $3500 per carat, at retail prices.

Keep in mind the above guidelines and you will not go wrong while buying a topaz. Always take time and examine the gem before purchase – its your money after all. The topaz is an alluring yet comparatively inexpensive gem that can be used to great advantage in jewelry settings.