Related to marble, onyx forms under the slow drip of water in cool, dark limestone caverns. A fragile, delicate stone webbed with elegant bands of colour, it is often translucent and can shine especially beautifully when backlit. Romans and ancient Egyptians used alabaster, a type of onyx, for fine sculpture and drinking vessels. It still adorns the interiors of mosques and palaces across the Middle East, including the Alabaster Mosque in Cairo’s Citadel. Onyx stone is a very different substance from the mineral onyx, famed as a gemstone and healing crystal. But, like a gemstone, its precious sheen is best suited as an accent. favouronyxfor