Extraordinary Gemstones · 02
Star Sapphire
Light, gathered into six rays
Some sapphires carry a phenomenon within them: a star of light that glides across the dome of the stone, assembling and dissolving as the light source moves. The ancients read it as a guardian; gemmologists read it as silk.
Asterism is the work of rutile, needle-fine crystals aligned along the corundum's threefold symmetry. Cut en cabochon above such silk, the stone returns light as a six-rayed star that lives only in movement. No photograph fully captures it, which is precisely its charm.
From the House
Star Sapphire, in the house's hands
The Science
What the earth had to do
The mechanism
Microscopic rutile needles, exsolved within the crystal as it cooled over geological time, lie in three directions at 60 degrees to one another. Each set of needles scatters a band of light at right angles to its length; three bands crossing above a domed surface produce the six-rayed star.
Why cabochon
A star sapphire is never faceted. The lapidary's art lies in orienting the dome precisely over the silk so that the star stands centred, sharp and mobile, a decision made once, and irreversibly, on rough of great value.
The rarest combination
Asterism paired with colour change, blue in daylight, violet under incandescent light, is among the rarest phenomena in corundum. A stone holding both, at significant size, untreated, is a once in a generation object.
Provenance
Where the finest come from
Burma (Myanmar) is the classic source of fine star sapphire, alongside Ceylon (Sri Lanka). The world's most famous examples, including stones held by great museums, trace to these deposits.
Collecting
How collectors judge it
The measure of a star sapphire is the star itself: its sharpness, its centring, the way it rides the dome, then body colour, translucency, size, and above all the absence of treatment. Documented Burmese stones of scale stand at the summit of the category.
The Genesis Perspective
The Star of Genesis is the house's namesake masterpiece: a natural colour change star sapphire of 48.95 carats, Burmese, untreated, its six-rayed star documented by the Gübelin Gem Lab under Report No. 24057232 with a Gemstone Rating of 93.7, Outstanding.
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Whether you are searching for an extraordinary natural gemstone, commissioning a bespoke creation or seeking expert guidance, we look forward to hearing from you.