Collecting 101

1.

The Difference Between Jade and Jadeite

Jade is the common family name for two types of gemstone: jadeite and nephrite. While nephrite has been used in China for millennia, jadeite was only introduced from the remote mines of Burma in the late 18th century. It was not until 1863 that the distinction between the two stones was made, when French mineralogist, Alexis Damour, discovered that they are made of different mineral compositions.

Nephrite is traditionally used for ornaments, whereas jadeite’s vibrant colours and delicate translucency make it a highly prized material for jewellery. Jadeite is the rarer, more valuable stone of the two, and is the only type of jade presented at Bonhams jewellery sales. Whether you are just starting your collection or you are a jadeite connoisseur, Bonhams will have the jewel for you. Our sales cater to all collectors by offering a varying price range of jadeite jewellery; recently a pair of jadeite earrings sold for HK$8,925 (under £900), while a fine two-strand jadeite bead necklace reached HK$6,520,000 (over £600,000).

2.

Colour

Most jadeite is green, and it remains the most sought-after colour. The preferred hue can be a personal aesthetic choice; collectors may be drawn to Apple green or Emerald green, but it is accepted that the finest quality jadeite is a pure, Imperial green. This deep, intense colour has a slightly yellow hue, with no blue or grey modifiers. Jadeite comes in various colours, including lavender, which is becoming increasingly popular with collectors.

When assessing jadeite, there are three important colour considerations. The first is saturation: generally, the more saturated or vivid the hue, the more valuable the stone. Descriptors such as “vibrant”, “sharp”, “bright” or “hot” all indicate a well-saturated stone. The second is tone: a medium tone is ideal, rich enough to create an impact, but not so dark that light cannot pass through the stone. The third key term is distribution: this means that colour should be completely even to the unaided eye. Any specks, veins or mottling that detracts from the overall appearance will reduce the value of the stone.

3.

Clarity

Much of the allure around jadeite is the subtle glow of the stone as the light passes through it. Any inclusions that obstruct the passage of light through the stone will therefore impact its value. Typical imperfections are mineral inclusions – dark specks in the stone – or cloudy patches that are visible under a strong light. While jadeite is a relatively hard stone (it is 6.5 to 7 on the Mohs scale) and has exceptional toughness, it is still a gemstone and needs to be worn and treated with care. Any fractures or chips in the jadeite, whether healed or unhealed, can severely reduce the value of the item.

4.

Translucency and Texture

The translucency of jadeite can vary tremendously, from semi-transparent through to opaque, depending on the texture of the grain. The most valuable stones have a consistent semi-transparency throughout, produced by a very fine grain. In these examples, such as Imperial green jadeite, light can penetrate the gem and create a soft radiance from within. Opaque stones are formed of coarser grain, which cannot catch the light in the same way, and are of significantly lower value.

5.

Cut (Fashioning)

The most popular cuts are cabochons, beads and bangles. Other popular styles of jadeite jewellery include saddle rings, double or triple hoop earrings, and huaigu (a flat disk with a hole in the centre). The jadeite used for carvings tends to be of lower quality; however, with skilful craftmanship, these designs can make attractive pendants or objets d’art.

Cabochons

A cabochon is a stone that has been polished but not faceted, to create a smoothly curved dome. The proportions are important: the stone should have an aesthetically pleasing length-to-width ratio. The most valuable cabochons have both a convex top and base, known as a double cabochon. Those that have a concave or hollow base are the least valuable. You’ll find cabochons in earrings, pendants and rings.

Jadeite Beads

In beaded necklaces, it’s all about symmetry: each bead should be identical in colour, size and shape – even the drill holes should be symmetrical. The most valuable necklaces are strands of uniform beads, rather than graduated beads. The longer the strand and the larger the beads, the higher the value. It’s important to examine each bead closely, to check that the hole drilled through the centre hasn’t caused any cracks to appear.

Jadeite Bangles

Arguably the most skilful form of jadeite jewellery is the classic bangle. This item is known as a hololith, meaning it is made from a single piece of stone. To make a bangle of uniform hue and transparency is an achievement; it requires exactly the right rough material and tremendous skill. Accordingly, bangles hold an inherent value. This is enhanced by certain factors: a curved surface is more desirable than flat, a pair of bangles adds a premium, and bangles with an inner diameter of 54-58mm are most in demand. As with beads, a crack in the bangle can have a detrimental impact on the item’s value.

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