The Crystal Gazette. Vol 51 # 11 November 2012 STONE OF THE MONTH (modern) Citrine and Topaz. Citrine Mystic Topaz

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1 The Crystal Gazette Vol 51 # 11 November 2012 STONE OF THE MONTH (modern) Citrine and Topaz Citrine Rough Topaz Rough Citrine Mystic Topaz Notices and Phone Nos Management Committee Meeting: Thu 18th Nov 2012, Room 428, 38 Gawler Place, 6 pm. President: Sue Arthur, FGAA,Dip DT,Cert IV T&A, M Secretary: Sandra Pimlott, FGAA, Dip DT Ph Treasurer: Don Bennett B.E. FGAA Ph Education: Tanya Cerny FGAA M Lise Jensen FGAA M

2 SA/NT Celebrate the Holidays Wednesday, 21 November 2012 Saracen's Head Hotel, Adelaide SA Relax, chat and catch up with industry colleagues to celebrate the holidays When: Wed 21 st Nov, 2012 The cost will be $15 for JAA members, $20 for non JAA members. Apprentices are Free Food and 1 raffle ticket is included. Drinks are not included. Lots of Prizes!!!! Raffle Tickets on Sale $2 ea or 3 for $5.00 The Crystal Gazette Is Going Online!! From July, the Crystal Gazette will be on the GAA website in printable PDF format. You can also have your Crystal Gazette ed to you in PDF format, rather than mailed to you in hard copy. If you would prefer a paper hard copy sent out to you, rather than in format, please your preference to Tanya Cerny at tanya@australianpublications.com The most famous topaz in the world is a colourless stone known as the "Braganza Diamond" set in the Portuguese Crown Jewels. Originally thought to be a diamond, it weighs a whopping1680 carats. The world's largest faceted gemstone is the "El-Dorado Topaz", weighing 31,000 carats (equivalent to 6.2 kg). When first discovered in Brazil in 1984, the rough "El-Dorado" crystal actually weighed 37 kg; a total of 30.8 kg of stone was cut away to reveal a final stone of perfect cut, clarity and golden colour.

3 Notes & Reminders TO REGISTER for any GAA course PLEASE CONTACT: Education: Tanya Cerny FGAA,. M or Lise Jensen FGAA M or Secretary Sandra Pimlott , sandrapimlott676@hotmail.com To All Gem 1, Gem 2 and Diamond Technology Students. A big Thank You from myself for being so enthusiastic, keen and interested in gemmology. It has been a pleasure to assist you all along the path of learning about this fascinating course. I hope you all keep in touch with the association and wish you all the best. Sandra 2013 Courses Commencing dates Please note there has been a price increase in some courses. 1. Gemmology Diploma Gem1 February - $2950 M, $3450 NM 2. Gemmology Diploma Gem2- February - $2750 M, 3250 NM 3. Intro to Gemmology Jan 12 th & 19th, Apr, Aug, Nov- $ Diploma Diamond Technology-March- $3250( Incl Dia Grading)* 5. Diamond Technology- $ Diamond Grading TBA-$1750* 7. Advanced Diamond Grading TBA-$ Gemmology Update- $2750* 9. Retail Diamond Consultancy- TBA- $ Pearl & Bead threading- TBA- $245 M $265 NM 11. Intro to Antique Jewellery- TBA-$275 *Course offered depending on numbers enrolling Note :- Prices given are members prices- Non-members please contact Secretary for prices ROOMS ATTENDANCE AND VOLUNTEERS Please note that attendance at the rooms on Fridays for cataloguing, testing of stones, qualified members use of instruments and students extra study/practical opportunities has commenced. Extra volunteers to assist are welcomed. Or just come down for a chat and coffee. If it has been a while since you have looked down a microscope, come in and reignite your passion for gemmology Second Hand Books for students - We are nearing the end of another year. If you want to sell your gemmology study books please contact the Secretary. Typical are Gems Webster, Gemstones of the World Schumann, also Read, Bruton, Nassau, Liddicoat any edition MONTHLY MEETINGS: There will be no Friday Night meeting. However, the combined Chrismas Party and Quiz night is coming up on Saturday November 17th. 3

4 NEW DEVICE IDENTIFIES DIAMOND-RICH ROCK A new device developed by the Universities of Johannesburgand Witwatersrand in South Africa with help from engineering company Bateman will be able to identify the presence of diamonds buried inside other rocks, Mining.com reports. The machine, called MineralPET, uses nuclear technologies to verify the internal atomic makeup of a substance, using gamma rays, according to Mining.com. The device is said to be able to be able to tell the difference between the various kinds of minerals that can result from carbon, whether they be graphite, coal, or precious diamonds. At present, the MineralPET is expensive to produce, but those involved with the project say that they mean to figure out ways to reduce costs and eventually produce an financially viable version, which could have a significant impact upon the diamond industry worldwide, both economically and ecologically November Crossword- Test your Knowledge Across 1, Australian diamond, synonymous with pink coloured diamonds. (6) 5 6, A type of andradite garnet, (9) 8, Hardness Scale. (3) 11, A type of material that diamonds may be found in. (9) 12, Ancient term for garnet, particularly when cut en cabochon with a hollow back(9) Down 8 1, Colouring due to a trace impurity in the basic chemical composition of 9 the mineral. (13) , Section of cut stone, that divides the top section from the bottom section (6) 12 3, A bicoloured quartz, that is amethyst on one end and citrine on the other. (8) 4, An instrument designed to measure birefringence and optic character of gemstones (13) 5, A doubley refractive stone, where the 2 light rays vibrate at right angles to each other. (8) 7, A type of secondary deposit where gemstones may be found (8) 9, All the faces which are identically related to the crystal axes. (4) 10, A hemisherical shaped pearl which is grown against the inside of the oyster shell. (4) 4

5 Gem Of The Month Topaz and Citrine Topaz is a silicate mineral of aluminium and fluorine with the chemical formulaal2sio4(f,oh)2. Topaz crystallizes in the orthorhombic system, and its crystals are mostly prismatic terminated by pyramidal and other faces. Color and varieties Pure topaz is colorless and transparent but is usually tinted by impurities; typical topaz is wine, yellow, pale gray, reddish-orange, or blue brown. It can also be made white, pale green, blue, gold, pink (rare), reddish-yellow or opaque to transparent/translucent. Imperial topaz is yellow, pink (rare, if natural) or pink-orange. Brazilian Imperial Topaz can often have a bright yellow to deep golden brown hue, sometimes even violet. Many brown or pale topazes are treated to make them bright yellow, gold, pink or violet colored. Some imperial topaz stones can fade on exposure to sunlight for an extended period of time. Naturally occurring blue topaz is quite rare. Typically, colorless, gray or pale yellow and blue material is heat treated and irradiated to produce a more desired darker blue. Mystic topaz is colorless topaz which has been artificially coated giving it the desired rainbow effect. Localities and occurrence Topaz is commonly associated with silicicigneous rocks of the granite and rhyolite type. It typically crystallizes in granitic pegmatites or in vapor cavities in rhyolite lava flows like those at Topaz Mountain in western Utah. It can be found with fluorite and cassiterite in various areas including the Ural and Ilmen mountains of Russia, in Afghanistan, Sri Lanka, Czech Republic, Germany, Norway, Pakistan, Italy, Sweden, Japan, Brazil, Mexico; Flinders Island, Australia; Nigeria and the United States. Colorless and light-blue varieties of topaz are found in Precambrian granite in Mason County, Texas within the Llano Uplift. Quartz-Citrine is an abundant mineral in the Earth's continental crust. It is made up of a continuous framework of SiO4 silicon oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO2. There are many different varieties of quartz, several of which are semi-precious gemstones. Crystal habit and structure Quartz belongs to the trigonal crystal system. The ideal crystal shape is a six-sided prism terminating with six-sided pyramids at each end. Occurrence Quartz is an essential constituent of granite and other felsic igneous rocks. It is very common in sedimentary rocks such as sandstone and shale and is also present in variable amounts as an accessory mineral in most carbonate rocks. It is also a common constituent of schist, gneiss, quartzite and other metamorphic rocks. Because of its resistance to weathering it is very common in stream sediments and in residual soils. Quartz occurs in hydrothermal veins as gangue along with ore minerals. Large crystals of quartz are found in pegmatites. Well-formed crystals may reach several meters in length and weigh as much as 1,400 pounds (640 kg). Citrine is a variety of quartz whose color ranges from a pale yellow to brown. Natural citrines are rare; most commercial citrines are heat-treated amethyst. Citrine contains traces of Fe3+ and is rarely found naturally. The name is derived from Latin citrina which means "yellow". Ametrine also known as trystine or by its trade name as bolivianite, is a naturally occurring variety of quartz. It is a mixture of amethyst and citrine with zones of purple and yellow or orange. Almost all commercially available ametrine is mined in Bolivia, although there are deposits being exploited in Brazil and India. The colour of the zones visible within ametrine are due to differing oxidation states of iron within the crystal. The different oxidation states occur due to there being a temperature gradient across the crystal during its formation. Artificial ametrine can be created by differential heat treatment of amethyst

6 Southampton scientists change the colour of gold Scientists in Southampton are now able to change the colour of gold. The technique involves embossing tiny raised or indented patterns on the metal's surface which alters the way it absorbs or reflects light. Prof Nikolay Zheludev, who leads the nanophotonics and metamaterials team at Southampton University, said it means gold can be made red or green or a multitude of other hues. It can also be applied to other metals such as silver and aluminium. The shape, height and depth of the embossed patterns determines how light behaves when it hits the metal and therefore what colour is created, said Prof Zheludev. "This is the first time the visible colour of metal has been changed in this way. "The colours of the objects we see all around us are determined by the way light interacts with those objects. Security feature "For instance, an object that reflects red light but absorbs other wavelengths will appear red to the human eye. "This is the fundamental principle we have exploited in this project. By embossing metals with patterns only around 100 nanometres across, we've found that we can control which wavelengths of light the metal absorbs and which it reflects." Prof Zheludev said the team is trying to market the technique, which could be used in jewellery making, commercially. He believes it could also be incorporated into documents and banknotes as a security feature because the metals are difficult to forge. Details of the research have been published in the journals Optics Express and the Journal of Optics.. The scientists received funding from the Engineering and Physical Sciences Research Council as part of a 5m project looking at photonic nanostructures. The colours of the gold were changed to spell out "Nano Meta" - pictured here through a microscope ALROSA Finds 888-Carat Industrial Diamond By Ricci Dipshan RAPAPORT...ALROSA unearthed an carat industrial diamondat its Aykhal Mining and Processing Complex, the company told Interfax. The diamond, while not gem-quality, is opaque and greenish-gray in color, with dimensions of 2.2 inches by 1.9 inches by 1.4 inches, and the fourth largest diamond produced in Russian by mass, according to Interfax. In September, ALROSA produced a carat gem-quality diamond at its Nyurbinsk Mining and Processing Complex, which has an estimated value of $1.5 million. 6

7 Study of New Method for Adding Fire to Diamonds Al Gilbertson GIA Laboratory, Carlsbad A new method of increasing the visual perception of fire in diamonds has been developed using nanotechnology techniques developed at the California Institute of Technology (Caltech). This new method, called Nanopolish or Nanocut, places unique optical structures on the surface of a diamond to increase the appearance of fire. As in traditional diamond cutting and polishing, only material on the surface is removed nothing is added or altered within the diamond. The additional fire results from a diffraction grating pattern etched into portions of the surface. This diffraction grating separates light into its spectral components, causing incident white light to appear as flashes of colored light. Details of the Nanopolish process and visual observation studies of these diamonds have been submitted for possible publication in Gems & Gemology. This 0.46 ct round brilliant diamond has small areas on the pavilion etched with diffraction gratings that increase its apparent fire. Photo by Robert Weldon This scanning electron microscope (SEM) image (magnified over 4500 ) exhibits the parallel etched lines of the diffraction grating etched on the diamond s surface. A. Gilbertson. Study of new method for adding fire to diamonds. News from Research, October 27,

8 Progress made toward turning Greenland into major producer of rubies For many, Greenland is but a vast icy expanse viewed from the airplane window as one crosses the Northern Atlantic between Europe and North America. In fact it is North America's third largest territory, after Canada and the United States. Some 81 percent is covered by an ice sheet and it has a total population of about 58,000. Nonetheless Greenland appears poised to become the world's next major producer of rubies. Leading the project is True North Gems, Vancouver-based public junior exploration company that is dedicated to the exploration and development of colored gemstone deposits in the permafrost areas of North America. True North's Fiskenaesset Ruby Project is located on the southwest coast of Greenland, about 160 kilometers south of the capital Nuuk. The property covers 823 square kilometers, with True North Gems owning 100 percent of the property licenses. Both ruby and pink sapphire have been found on the property, with a number of stones weighing more than 400 cts. According to the company the material is of high grade, with valuations of individual rubies climbing higher than $3,200 per ct. Pink sapphires from the site have been valued at $460 per ct. Rubies typically are extracted from alluvial deposits, but in Greenland they are still located within the original bedrock. This means that that they first need to be physically separated from the host rock in which they are contained. The process begins with crushing, where machinery compresses and squeezes the material so that it breaks down along natural fractures, rather than aggressively breaking the rock and any rubies that may be contained within it. The ruby and waste material is then sent through a gravity wash plant, where the lighter-weight waste minerals are separated from the denser ruby. Sorting is done using sophisticated optic systems, in which specialized cameras can detect the specific red color of ruby from the surrounding material. Small air jets then are activated which remove the ruby from the rest of the material. The result is two piles of material, one made up entirely of ruby, and one containing only waste. In recent years optic sorters have become developed enough to separate shades of pink and red from each other and also relative transparency, allowing a rough stone sort to be completed entirely by mechanized processes. According to True North, the complicated process of obtaining mining permits is in its final phases, and in August the company reported that the formal translation of the Social Impact Assessment report has commenced into both Greenlandic and Danish. While Greenland is formally North American, it is politically and culturally associated with Europe and more specifically Denmark. Greenland has formally been part of the Danish realm since 1953, but in 1979 it was awarded home rule and in 2008 its citizens voted to transfer more power from the Danish royal government to the the local Greenlandic government. "As we complete the final steps leading to production, the translation into both Greenlandic and Danish will allow all public meeting attendees the opportunity to fully appreciate the steps that have been taken by True North Gems to develop an economically sustainable mining through to production business plan, maximizing the positive benefit to Greenland"," said Nicholas Houghton, president and CEO of True North. The rubies discovered at the Fiskenaesset Ruby Project are still located within the original bedrock. This means that that they first need to be physically separated from the host rock in which they are contained. 8

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10 Come along to the: GAA Combined Xmas Party and Quiz night DATE: 17th November 2012 TIME: 6.30pm for 7pm start LOCATION: Lithuanian House 6 Eastry St Norwood CONTACT: Ivana Kneipp: Sue Arthur: Only $15 entry fee, Children $7.50 BYO supper & drinks, Tea and coffee supplied BOOK NOW, FOR A FUN NIGHT OUT! Money raised will go towards the GAA stand at the Skillex Careers and Training Expo in 2013 Enterance to the car park is via Oxford Place 10

11 TERACAST Diamond Merchants T F Suite 403, 38 Gawler Place Adelaide SA louise@teracast.com.au Contact Louise Citrine, the pale yellow gem belonging to the quartz species is considered an alternative to topaz as the birthstone for November. Named from the French word for lemon, citrine has the advantage of being a very affordable gemstone thanks to its ready availability. In ancient times, citrine was carried as a protection against snake venom and evil thoughts. Crossword Answers: Across 1 Argyle, 6 Demantoid, 8 Moh, 11 Lamproite, 12 Carbuncle Down 1 Allochromatic, 2 Girdle, 3 Ametrine, 4 Refractometer, 5 Uniaxial, 7 Alluvial, 9 Form, 8 Mabe

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