This 2.72ct natural alexandrite cat's eye is one of the rarest gemstones in existence, a stone that exhibits not one but two optical phenomena simultaneously. Alexandrite's legendary colour-change shifts from green-blue in daylight to red-purple under incandescent light, while the cat's eye (chatoyancy) effect produces a sharp, luminous band of light that glides across the cabochon surface as the stone moves.

Alexandrite displaying both colour-change and chatoyancy in a single specimen is exceptionally uncommon. Most alexandrite shows colour-change alone; most cat's eye chrysoberyl shows chatoyancy alone. When both phenomena appear together with this level of clarity at 2.72 carats, the result is a stone of genuine museum-grade rarity.

Origin & Certification

This alexandrite originates from Madagascar, which has emerged as one of the most important modern sources of fine alexandrite since the depletion of the original Russian deposits in the Ural Mountains. Madagascar produces alexandrite with strong colour-change characteristics, and the island's chrysoberyl deposits have gained recognition among gemologists and collectors worldwide.

The Ceylon Gem Lab (CGL) has certified this stone, confirming its identity as natural alexandrite (chrysoberyl variety), its colour-change properties, and its chatoyant (cat's eye) effect. CGL is an established gemological laboratory, and their certificate provides independent verification of this stone's extraordinary dual phenomena.

Understanding Alexandrite Cat's Eye

Alexandrite is the colour-change variety of chrysoberyl, one of the rarest mineral species used in jewellery. Its colour-change is caused by the way chromium ions in the crystal structure absorb light differently under varying illumination:

• Daylight / fluorescent light: The stone appears green to blue-green
• Incandescent / candlelight: The stone shifts to red, purple, or raspberry

The cat's eye effect (chatoyancy) is caused by fine, parallel needle-like inclusions within the stone. When cut as a cabochon, these inclusions produce a concentrated band of light, the "eye", that moves across the surface as the stone is tilted. This phenomenon requires skilled cutting to centre the eye properly.

For a single stone to display both phenomena with clarity, the crystal must contain both the chromium responsible for colour-change and the parallel inclusions responsible for chatoyancy, a geological coincidence that occurs extremely rarely.

Why This Alexandrite

At $3,500 AUD, this 2.72ct alexandrite cat's eye represents a rare opportunity to acquire a dual-phenomenon gemstone at an accessible price point. Fine alexandrite without cat's eye effect routinely sells for $5,000-$20,000+ per carat at auction, depending on origin and colour-change strength. Specimens that also display chatoyancy command further premiums among specialist collectors.

This stone's cabochon cut is the only cut that can display the cat's eye effect. Faceted stones cannot produce chatoyancy. The 8.09 x 7.75 mm proportions are near-round, providing an elegant, symmetrical presentation whether set in a ring, pendant, or displayed as a collector specimen.

Alexandrite has been called "emerald by day, ruby by night" since its discovery in Russia in the 1830s. Adding the cat's eye phenomenon creates a gemstone with no parallel in the mineral kingdom, a stone that shifts colour with the light and reveals a luminous eye when moved. For collectors seeking a genuinely unique acquisition, few stones can match this combination.

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