Important Notice

Centring on an oval-shaped cabochon purple star sapphire, with a surround of alternating square and round diamonds, mounted in gold. Stamped '18K'.
br..Star purple sapphire: 7.54 carats
Diamond: 1.12 carats
Gross weight: 7.88 grams


Ring size: American 6 3/4, English N

One of the oldest and best known coloured precious stones, sapphires are composed of a colourless material known as corundum. The deep blue colour most commonly associated with this gemstone is caused by the addition of titanium and iron during its formation. However, fancy sapphires occur in a varied spectrum of colours, including 'pink' sapphires, which can range from shades of red to purple.

Many sapphires contain inclusions, such as those which cause the stone to have a star-like appearance - a phenomenon known as asterism, originating from the ancient Greek word for 'star.' This effect is caused by thin mineral needles which are aligned such that they reflect and "scatter light, causing the coveted visual effect without negatively affecting the gem's transparency," and effectively increasing the value of the stone. "The best star corundum has a crisp, distinct star against strongly saturated colour," which is situated at the top of the stone, has straight rays, and moves smoothly across the surface. ("Sapphire Quality Factors," GIA, gia.edu, online) The stone must be cut as a cabochon to exhibit asterism, and the number of intersecting bands (usually 2, 3 or 6) determine the rays of the star. In the present lot, three streaks create a mesmerising six-ray star.

These luminous, highly durable stones were considered powerful and mystical talismans, bringing luck and protection to travellers and seekers. They were referred to by some as "the stone of destiny." According to legend, "The celebrated explorer Sir Richard Francis Burton travelled the Orient with a large star sapphire, known as an asteria. He found it brought him much luck, as the stone's fame preceded him in his travels. Many believed simply viewing the talisman meant good fortune." (Fara Braid, "Sapphire Symbolism," International Gem Society, gemsociety.org, online)

Some of the largest star sapphires in the world - including the blue Star of Adam (1404.49 carats), the greyish-blue Star of India (563.4 carats), and the violet-blue Star of Bombay (182 carats) - were mined in Sri Lanka, and the world's second largest star sapphire, Black Star of Queensland (733 carats) was discovered in Australia. Other significant locations of star sapphire deposits are Myanmar and Thailand.

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