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The Gem Detective: Pink Gemstones

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The Gem Detective: Pink Gemstones GEMS THE gem DeteCTIVE: PINK gemstONes the spodumene family, and salmon pink to orange-pink morganite from the beryl family are attractive and usually eye-clean. Both may be subjected to irradiation to create or intensify the colour. Spinel may occur in a light-toned pink similar to kunzite; however, the latter is separated by its strong pleochroism. Ever-popular sapphire and tourmaline are IATED L available in an enormous range of depths and S AFFI S intensities – synthetic sapphire is common L and easily distinguished from its natural counterpart using standard equipment. Next up is precious topaz, a rare and valuable collector’s gem. More commonly encountered is ‘pinked’ or heat-treated topaz. In its finest quality, pink topaz displays a purplish or red overtone and is called ‘imperial’. Be mindful that non-precious topaz may be coated to imitate precious varieties. IMAGE COURTESY OF BRENDAN MCCREESH, O’NEI MCCREESH, BRENDAN OF COURTESY IMAGE For pink gemstones of a more affordable nature, there is rose quartz, zircon and Pink transparent gemstones appeal to a Common imitations include synthetic cubic LOOK OUT rhodolite garnet. Rose quartz is distinguished wide range of tastes and also come in a zirconia, glass, synthetic moissanite, yttrium FOR SIMPLE by low dispersion and soft translucence while pink zircon is highly dispersive with a wide range of forms. From lavender to hot aluminium garnet (YAG) and synthetic spinel. YET EFFECTIVE pink, what could they be? MEGAN AUSTIN TREATMENTS, diamond-like lustre. Zircon displays strong Natural non-pink diamonds may also be SUCH AS THE sets out to investigate. doubling of the back facets, a property garnet irradiated and annealed to transform them APPLICATION OF A never displays. Begin the detective journey by compiling a to colour pink; synthetic or laboratory-grown PINK COATING TO Watch out for ‘composites’. Garnet-topped list of possible gemstone identities based on pinks are produced using Carbon Vapour WHITE DIAMOND doublets are composed of a hard garnet top colour and transparency. Deposition (CVD) or High Pressure High PAVILION FACET fused to a pink glass pavilion. The first and most obvious suspect is pink Temperature technology. Some less common pink gems include diamond. The exact cause of colour is still Look out for simple yet effective treatments, apatite, scapolite, danburite, zoisite, diaspore a mystery but may be related to plastic such as the application of a pink coating to and fluorite. deformation of the crystalline structure. Most white diamond pavilion facets. Coatings may polished pink diamonds are well under a range from a high-tech vacuum-sputtered These pink gemstones are just the beginning carat but are rare, beautiful and valuable. film to a crude dab of pink nail varnish. While of your gemmological journey; there are Australia’s Argyle Diamond Mine, which sophisticated treatments and synthetics are many more to consider. Consult your local supplies more than 90 per cent of the identified using advanced spectroscopic qualified gemmologist or registered valuer for i world’s pink diamonds, classify pink diamond analysis, simpler treatments like coatings can their expertise. according to colour – purplish pink, pink, pink be detected using standard magnification. Megan Austin FGAA FGA Dip DT BA, is an in- rose or pink champagne – and intensity. Next on the pink checklist are two large, house gemmologist and registered valuer for Consumers should be aware of any luxurious gemstones renowned for their a retail jeweller. For more information about treatments, synthetics and imitations. pastel tones. Pale pink to lilac kunzite from gemstones, visit: gem.org.au March 2015 Jeweller 51.
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