Moonstone, the alluring pale gemstone, is known for its attractive pearly sheen and is so named for its resemblance to the moon. It is a transparent to translucent gem, with a base colour which is often pale or colourless. Moonstone is usually cut as a cabochon as this best displays its special characteristic which is known as ‘adularescence'. This effect of a billowing sheen which moves over the surface of the gem when under a light source is caused by the internal construction of the gemstone.
Moonstone belongs to the mineral group feldspar- a mineral which makes up almost two thirds of all Earth's rocks. There are two varieties of feldspar which create moonstone- albite which is uncommon and orthoclase which is more prevalent. Sri Lanka is its major source of the best quality moonstone.
Moonstone has a long history- the Ancient Romans believed it was made up of the rays of the moon and identified it with lunar deities, such as the goddess Diana. Pliny, the Roman historian, thought that moonstone changed appearance with the phases of the moon- astonishingly a belief which persisted until the 16th century! In India, moonstone was a sacred stone, and was a traditional wedding gift as it was thought to bring harmony to the marriage.
Moonstone set jewellery was especially popular in the Victorian and Art Nouveau periods. French glass and jewellery artist, René Lalique, experimented with the subtle shimmering colour of the moonstone set within the ‘whiplash' free flowing designs of the Art Nouveau period.