Moonstone

Indeed it owes its name to that mysterious shimmer which always looks different when the stone is moved and is known in the trade as 'adularescence'. In earlier times, people believed they could recognise in it the crescent and waning phases of the moon.

Moonstones from Sri Lanka, the classical country of origin of the moonstone, shimmer in pale blue on an almost transparent background. Specimens from India feature a nebulous interplay of light and shadow on a background of beige-brown, green, orange or brown.

These discreet colours, in connection with the fine shimmer, make the moonstone an ideal gemstone for jewellery with a sensual, feminine aura. This gemstone was very popular once before, about a hundred years ago at the time of Art Nouveau.

It adorns a noticeably large number of the jewellery creations of the French master goldsmith René Lalique and his contemporaries, mainly to be found in museums and collections today.

This gemstone is surrounded by a good deal of mystique and magic. In many cultures, for example in India, it is regarded as a holy, magical gemstone. In India, moonstones are also regarded as 'dream stones' which bring the wearer beautiful visions at night. In Arabic countries, women often wear moonstones sewn out of sight into their garments, for in their cultures the moonstone is a symbol of fertility.

The moonstone symbolises our being in its entirety. With its soft shimmer, it strengthens our emotional and subconscious aspects. The associations connected with that make it a "lovers' stone", evoking tender feelings and safeguarding the true joys of love. It is also said that wearing a moonstone strengthens our intuition and our capacity to understand.

This enchanting gemstone belongs to the large mineral group of the feldspars, of which almost two thirds of all the rocks on Earth consist. The moonstone is actually the feldspar variety known as 'adularia', a potassium aluminosilicate of gemstone quality, which is also found in the European Alps near the Adula Group – hence the name 'adularia'. Another synonym for moonstone is 'selenite', from the Greek 'selene' ('moon').

In their uncut state moonstones are rather unprepossessing and afford little idea of what it is that actually constitutes their charm: that mysterious shimmer of light. For that shimmer is not really shown to advantage until the art of the cutter has been brought to bear.

Classical moonstones are always cut as cabochons, the most important thing being the correct height of the stone. The cutter must also align the axes of the crystal precisely into the zenith of the stone, for that is the only way in which he will bring about the desired light effect.

Traditionally, the classical moonstones, almost transparent and with their bluish shimmer, come from Sri Lanka. However, they are also found in the USA, Brazil, Australia, Myanmar and Madagascar. Since bluish moonstones of good quality have been becoming more and more of a rarity in recent years, prices have risen sharply.

For a few years, there have also been some green, brown and orange specimens on the market, as well as some with a smoky colour and some the colour of champagne, and some black and some reddish ones, mainly originating from India.

Some have a cat's eye effect or a four-spoked star as well as the typical undulating shimmer of light. These stones are not only cut as cabochons, but also as artistic cameos or engraved with the faces of children, the moon or grotesques. But they too have the shimmer of light typical of the moonstone, as do the beads which are cut from suitable raw material for gemstone necklaces.

The shimmer of light of the moonstone is something very special in the fascinating world of gemstones. Specialists refer to the phenomenon as 'adularisation'. The cause of it is the lamellar inner construction of the gemstone. Incident light rays are refracted and scattered in the stone. In this way, a unique light effect comes about, and it is this which makes the moonstone so distinctive and so desirable.

However, this beautiful gemstone does have one weak point, and that is its relatively low hardness of only 6 on the Mohs scale. For that reason, moonstones should be handled with care, for they are sensitive. Having said that, minor flaws such as may occur when the stone has been worn for some time are quite easy to remedy.

A jeweller can have a moonstone which has grown matt repolished, after which it will shimmer again just as it did on the very first day.

When purchasing moonstone jewellery you will come across the most astonishing price differences. The more intense in colour, the larger and the more transparent, the more highly valued the moonstone. Really fine blue specimens display an incredible 'three-dimensional' depth of colour which the observer does not really come to recognise until the stone is moved about in a playful way.

Specimens of that kind are highly esteemed on account of their rarity and their prices are correspondingly high. The colourful Indian moonstones, on the other hand, are not only very much in fashion. They are also, as a rule, somewhat more reasonably priced than classical blue moonstones. This means that today, anyone can select the moonstone to suit his or her taste and pocket.

Moonstones are treasures of Nature with a sensual and seductive aura. Not only do they like to be looked at and admired a lot; they also thrive on being worn and moved about a good deal, for only then can the soft shimmer of light which makes this gemstone so desirable really come into its own.

^{Top image: 1. Photo by Ken Larsen. 2. Photo by Chip Clark. Both courtesy of The Smithsonian Institution Geo Gallery.}