The beauty of the Kashmir sapphire

For many gem lovers the Kashmir is the King of blue sapphires. Kashmir is the only place on earth where sapphires are found in the deepest blue hues, without any other overtones. Burmese sapphires have a navy tone and Sri Lankan (Ceylon) stones contain a hint of violet. Kashmir sapphires also have a unique, slightly opaque or 'milky' appearance due to fine needles or rutile within the stone which causes the light to refract, lending a softness to the tone whilst being small enough to not reduce the clarity. It is the combination of the colour with the softness of tone that gives the Kashmir sapphire its unrivalled appearance. If this didn't make the stone rare enough, the Kashmir region has been largely depleted of the available sapphires within its rocks and the principle mine has not produced any large stones since the second world war. As a consequence of this we are unlikely to see any new examples appearing on the market. Furthermore, the majority of the stones in existence were mined in the days of British colonial rule back in the 1880s and more than a century has passed since they came onto the market. Due to the climate in the Himalayas mining was only possible for three months of the year so the difficulties involved in removing the stones from the ground with nineteenth century technology were profound.

(Princess Diana and later the Duchess of Cambridge wearing the same Kashmir sapphire ring)

The mining area of Kashmir is extremely remote, being reported as the "region beyond the snows" by early explorers. It's value to the ruling elite, the Maharajas, was such that they decided to forbid foreigners from entering the area. The mythology of the region is vast. One such example involves the discovery of the first sapphires by a native Shikari who mistakenly picked one up into order to strike a light to light his pipe! It is certain that at one point a landslide laid bare the granite rocks beneath the soil and exposed a number of blue sapphires. This resulted in a Laholi trader taking some samples to Simla (modern day Shimla) where the true value of the find was realised and the Maharajah of Kashmir dispatched a regiment of his soldiers to guard the site. The early years of production were rather chaotic ones and it was not until output began to fall in 1887 that the first comprehensive geological survey was conducted by French geologist T.D. La Touche. La Touche discovered that the mine was exhausted and he began to look instead for gem deposits produced as a result of weathering on the valley floor.

(Kashmir is a beautiful but remote and much fought over region)

As a result of this survey official mining operations reached a hiatus for over two decades before activity eventually resumed in 1906, the results of which were sporadic. In the mid 1930s further efforts were made to mine the area systematically and 641,656 carats of sapphires per annum were produced on average between 1933 and 1938, much of which turned out to be heavily included stones that were only fit for industrial use. Several efforts were made after this point but no significant production ever occurred again. Due to the geopolitical situation of Kashmir and the tensions that exist in this region between Pakistan and India, more recent surveys have been severely hampered. As a result of the lack of new Kashmir sapphires entering the market, the only way in which a jeweller or collector can get hold of them is via auction and private sales of antique gems and jewellery. This has created enormous demand for these rare stones and raised the issue of confirming the true origin of a gemstone.

(Kashmir is nestled between India, Pakistan and China in a volatile region)

Here science has come to the rescue! Dr Edward Gübelin, founder of the famous Gübelin laboratory and jewellery brand in Lucerne, Switzerland, developed the science of origin in the 1940s. He achieved this by examining a vast number of gems from around the world with known certified origin and he identified the key features and inclusions that were common to each group of stones from each part of the world. Thus gemmologists were now able to ascertain, with a reasonable degree of confidence, the true provenance of a stone based upon reference to Gübelin's meticulous research. Over the years this technique has been refined and enhanced by advances in modern technology and laboratory equipment, which has enabled further origin analysis by way of examining the chemical composition of a stone and mapping this against vast databases. In the case of a Kashmir sapphire the principle identifier is the distinctive colour. Natural blue sapphires are coloured by a combination of iron and titanium but if either of these are missing it can result in a milky white or colourless stone. Some sapphires are actually pink or purple and a few contain alternating colour saturations and clarities known as zoning. The more translucent areas of the Kashmir sapphire gives it its 'velvet' appearance.

(Eduard Josef Gübelin, the father of modern gemmology)

The best known corundum inclusion is that of the rutile, which can create star like asterisms deep within the gem. So called star sapphires from Kashmir are phenomenally rare and hence very valuable. Burmese and Ceylon sapphires have heavier rutile needles which gives off a silky appearance, which is their hallmark. In the case of the Kashmir sapphire a very powerful microscope is required to even identify the individual crystals of the fine inclusions. The effect this has is to scatter the light that enters the stone, giving it a slightly hazy quality without affecting its transparency. This haziness created by the rutile crystals combines with the velvety appearance that is caused by the zoning within the gemstone to create a cacophony of hues and colour that is exquisite to the eye. It is the uniqueness and rarity of the Kashmir sapphire that makes it so desirable. Given the remarkable combination of factors that have gone into creating them, it is little wonder that these beautifully elegant deep blue stones are the peerless paragons of the coloured gemstone market.

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