Chrysoberyl
Chrysoberyl is a mineral composed of beryllium, aluminium and oxygen, occurring mainly in yellow, golden, green and brown hues. Despite its name, it is a separate mineral from beryl — the family that includes emerald and aquamarine.
Gemological properties
| Material | An oxide mineral |
|---|---|
| Chemical formula | BeAl₂O₄ |
| Crystal system | Orthorhombic |
| Colour | Yellow, golden, green, yellowish green and brown; alexandrite displays colour change |
| Transparency | Transparent to translucent; heavily included material may be opaque |
| Lustre | Vitreous |
| Hardness | 8.5 on the Mohs scale |
| Specific gravity | Approximately 3.73 as a reference value |
| Refractive index | Approximately 1.746–1.756 |
| Birefringence | Approximately 0.008–0.010 |
Values may vary slightly with the stone’s composition.
Chrysoberyl, cat’s-eye and alexandrite
Transparent chrysoberyl without a special optical phenomenon is often faceted to highlight its colour and light return.
Cat’s-eye chrysoberyl displays a concentrated band of light that moves across the stone as the lighting or viewing angle changes. This phenomenon, called chatoyancy, results from light reflecting from parallel inclusions within the stone. A correctly oriented cabochon cut brings out the band. Not all chrysoberyl displays a cat’s-eye, and the phenomenon also occurs in other minerals.
When the name ‘cat’s-eye’ is used without another mineral name, it conventionally refers to chrysoberyl displaying this phenomenon.
Alexandrite is the colour-change variety of chrysoberyl. Typical stones change from green or bluish green in daylight to purplish red under incandescent lighting. Some stones combine colour change and a cat’s-eye. Alexandrite has a separate page on our website.
What distinguishes a fine cat’s-eye?
In a stone with a well-developed effect, the band of light appears sharp, distinct and continuous. In some stones, under suitable lighting, one side looks pale and milky while the other is darker and honey-coloured — an appearance known as milk and honey. Body colour, transparency, the position of the band and cutting quality together influence the stone’s beauty.
Sources around the world
Chrysoberyl is known from Brazil, Sri Lanka, Madagascar, Russia and Zimbabwe, among other sources. In Sri Lanka it also occurs in alluvial deposits around Ratnapura, while Brazilian sources include Minas Gerais, Bahia and Espírito Santo.
Care and cleaning
Its high hardness gives chrysoberyl good scratch resistance, but does not make it immune to breakage. Protect it from impacts and clean with lukewarm water, mild soap and a soft brush. Cleaning should be adapted to the condition of stones with significant fractures or inclusions.
Spiritual and symbolic meaning
Cat’s-eye chrysoberyl is associated with a connection between willpower and the wisdom of the heart. It symbolises acting with confidence and sensitivity together — moving forward with determination while listening to ourselves and others. It is linked symbolically with the solar-plexus and heart chakras, and with generosity, compassion and personal responsibility.
In spiritual belief, it is also connected with abundance created through giving and flow, rather than accumulation alone. The cat’s-eye band can serve as a symbol of focus and inner vision: recognising opportunities, clarifying intentions and directing action towards a meaningful path.
Cat’s-eye in belief and Kabbalah-inspired jewellery
Cat’s-eye chrysoberyl is also familiar in the world of Kabbalah-inspired jewellery and segulot, where it is associated with abundance, blessings for livelihood and protection. Some people wear it as part of jewellery with personal and religious significance. These are attributions of belief, rather than proven gemological properties or a promise of financial success.
These meanings belong to the realm of belief and symbolism. They can give jewellery personal significance, but they are not proven gemological properties or a promise of healing, protection or a change in health.