History & Introduction

Topaz is a fairly common and an affordable gemstone. It is available in huge and flawless crystals that is faceted into huge gemstones with a weight of thousands of carats. The use of topaz goes back to Egyptian times when the ancient Egyptians believed that yellow topaz received its golden hue from the Sun God, Ra. Some believe that "topaz" is a Middle English word that was derived from the Old French word "Topace" and Latin "Topazus", the root of which is in the Greek word "Topazios" or "Topazion"; the ancient name of an island in The Red Sea where the ancient Greeks mined a yellow gem that they believed to be topaz. The name of the island in Greek says "to seek". It is named because it was difficult to find amongst the mist. This island is now known as "Zabargad" or "St John's Island", and ancient Greeks actually mined "chrysolite"the gem. The Old Testament in Christianity it makes references to topaz, however according to this gemstone may have also been "chrysolite", rather than topaz. The word "topaz" could also have stemmed from the Sanskrit (the ancient language of India) word, "tapas", which means "fire".

Topaz can be both very common (when clear or in certain colors such as brown that converts to blue when treated) and rarely (in case of natural beautiful colors rare to the species, example pink). Topaz became famous stems from the gem's good affordability and wear ability. Many times topaz is even altered with special surface treatments to give it unusual colors and iridescent effects, such as kiwi, ocean, mystic and orchid topaz. Topaz is the traditional birthstone for November.

Recognize - Topaz can be distinguished from sapphire, diamond, zircon, ruby, citrine, apatite, fluorite, kunzite, brazilianite, tourmaline and orthoclase by its hardness. Topaz possess less density and different chemical composition than chrysoberyl, and chrysoberyl possess no fluorescence, but topaz carries some weak fluorescence that is to differentiate the both. Even the beryl is mistaken for topaz, still it carries indistinct cleavage, whereas topaz shows perfect cleavage. Many less valuable gems are falsely sold as "topaz", for example, saffranite topaz, Madeira topaz, Palmeira topaz, occidental topaz, Rio topaz, smoky topaz, Scottish topaz and Spanish topaz. However, in many cases such stones like the citrine quartz, with the exception of smoky topaz. Indian topaz, king topaz and star topaz are all actually sapphire. Topaz is softer than ruby and sapphire. Topaz gemstone shows pleochroism that is the presence of different colors in a single stone according to the viewing angle.

Topaz makes an ideal gem. A good hardness and desirable colors, united with a relative abundance and accessibility creates it one of the most popular gemstones. The valuable colors of Topaz are the golden orange-yellow type, known as Imperial Topaz, and the orange-red colors and dark pinkish-red. Value increases with a deepness of color in orange and reddish hues. The common used colors of Topaz in jewelry are the blue. In the gem market till the last century blue Topaz became widespread, almost all the blue gem Topaz is heat treated and irradiated.

Availability - Deposits of topaz have been found in Brazil, Nigeria, Afghanistan, Australia, Myanmar (Burma), Germany, Japan, Madagascar, China, Mexico, Namibia, Russia, Zimbabwe, Sri Lanka, Pakistan, Ukraine and the USA. Natural light-blue topaz is available to the Northern Ireland and the UK. Huge topaz crystals are discovered in Ukraine and Minas Gerais (Brazil).

Usages - Topaz of all different colors are used in jewelry, in rings, pendants, earrings, bracelets and necklaces. The orange, blue and pink colors are frequently cut as gemstones and the colorless Topaz is getting more popular as an inexpensive Diamond simulant. Huge gems with faceted spheres are cut from big crystals that are flawless crystals and it helps them to convert to exquisite and exclusive collector’s items. Topaz is hardly cut into cabochons.

Buying Guide

Color - Topaz ranges from colorless (white) to yellow, light to pink to red, orange, red-brown and dark-blue, violet and light-green. Naturally colored topaz gets its color from iron and chromium; the impurities cause color, whereas pure topaz is colorless. Most unadulterated topaz is colorless or pale blue. The rare and valuable found topaz comes in yellow, or reddish-orange or pink, and is known as "imperial topaz" or "precious topaz". Some yellowish-brown topaz gems gets faded gradually when continually exposed to daylight. Red with violet topaz is very rare. Many topaz is treated in order to enhance the color. Reputable gem sellers declare any enhancements. The original stones are colorless or lightly colored, and the radiation method creates a deep sky-blue colors. In rare circumstances, some procedures of blue Topaz tend to fade slightly in exposure to sunlight after extended periods of time.

Clarity and Lustre - Topaz is transparent to translucent. It displays good clarity with less inclusions, thus topaz gemstones can be examined by the naked eye and found to be "eye clean" that means no imperfections is seen. Topaz is prized highly due to its brilliance and vitreous (glassy) luster.

Cut and Shape - Topaz is a very useful material. So, it is possible to cut into a many kinds of shapes, like octagon, square, oval, round, pear, heart and even fancy shapes like the fish or birds. Strongly colored gemstones are usually scissor cut whereas weakly colored stones are generally brilliantly cut. The facets presents the clarity and brilliance of the gem. As topaz has irregular inclusions, it is frequently cabochon cut. The hardness gives it resistant to scratches. But, lapidarists should handle topaz carefully because the perfect cleavage means that it is easily fracture.

Treatment - Topaz is often enhanced to produce the most desirable colors. The most popular color for topaz is blue, however the nature of blue topaz is usually pale blue instead of bright or deep blue. The topaz with a brilliant blue shades are usually achieved by artificial means. Topaz is exposed to radiation (a process known as irradiation) and then as usual heated, to create striking blue colors. A profound blue which is improved is called "London blue"; medium blue is called "Swiss blue" and light-blue is termed "sky blue". This blue color treatment is usually performed on greyish-blue or silver-grey gemstones. The darker blue shades are more valuable because more energy is needed to produce darker colors. Orange-brown topaz is heat-treated during a process known as "pinking", which produces a purplish-pink color. These processes are widely accepted, as they give the permanent color change, however, they should be declared by traders. Strict rules are followed related to the handling of irradiated gemstones, to see the safety of gem handlers as well as the buyers. Naturally pink topaz is rare and is usually a pale shade of pink found in Pakistan.

A thin coating of titanium dioxide vapour can be applied to topaz stones. Topaz can also be coated to change its color. Coatings are not permanent and can gradually fade with time. Stones that are treated in this way is not re-cut, as the coating will be removed and reveal a different, unwanted color inside. Coating treatment produces iridescent stones known as "mystic topaz". Topaz is even coated to give a bright pink color along with imitation "imperial topaz". White topaz is even shown to diffusion treatment that means it is exposed to chemicals as well as heat, to change the surface color. This treatment is done to make "green topaz", however the treatment gives a change to the surface color, therefore if the gem is re-cut, the original, undesirable color will be revealed. As with irradiation, any treatment on the surface or coatings are declared by reputable gem sellers. Natural topaz are also available.

Gemological Characteristics:

Chemical Formula	Al2SiO4(F,OH)2 Fluor containing aluminium silicate
Crystal Structure	Orthorhombic, prisms with multi-faceted ends, often octagonal in cross-section
Color	Colorless, yellow, orange, red-brown, light to dark blue, pink-red, red, violet, light green
Hardness	8
Refractive Index	1.609 - 1.643
Density	3.49 - 3.57
Cleavage	Perfect
Transparency	Transparent and translucent
Double Refraction or Birefringence	0.008 to 0.016
Lustre	Vitreous
Fluorescence	Under long wavelength UV, white and blue shows a weak yellow or greenish glow; brown, pink and yellow can show a strong orange-yellow glow; red shows a weak yellow-brown glow
SG	3.4 - 3.6
Mineral Class	Topaz

Classification:

• Blue topaz
• Sky blue topaz
• London blue topaz