For thousands of years, the people who manufacture and sell jade objects have found many ways to improve their appearance. Heat, wax, dye, bleach, acid, polymer injection and other treatments have all been used to improve the color, luster and stability of jadeite and nephrite. Although many of these treatments are part of traditional jade manufacturing processes, today’s serious buyers of jade want to know about all treatments that were used in the manufacturing process.
Commercial jadeite objects are placed into three “types” according to the treatments that have been used during the manufacturing process. They are designated as Type A, Type B and Type C jadeite.
Type A Jadeite
Type A jadeite objects have been treated with a coating of wax. This is the most traditional jadeite treatment. It is expected and accepted by serious buyers and generally does not impact the value of a jadeite object. In this treatment, manufacturers boil finished jadeite objects in water to clean them and prepare them for an application of wax. The objects are then dried and dipped into molten wax. The wax fills any surface-reaching pores and fractures. When the objects have cooled, excess wax is removed and the objects are buffed to a bright luster. The wax fills surface irregularities and gives the object’s surface a smooth, lustrous finish.
Type B Jadeite
Type B jadeite objects have been bleached by soaking in hydrochloric or sulfuric acid. The acid removes oxidation stains and leaches out sodium. This lightens the color of many materials. Pressure is then used to impregnate the jadeite with wax or a clear polymer resin. Impregnation fills all surface-reaching pores and fractures and gives the object an improved smoothness, luster and color.
Unfortunately, the appearance of Type B jadeite objects can begin to deteriorate in just a few years. Acid treatment makes some jadeite brittle, and polymer resins can discolor with time or exposure to heat and sunlight. Because of these problems, Type B jadeite treatment should always be disclosed when an object is sold, but many items are sold without disclosure. This lack of disclosure is because Type B jadeite objects normally sell for a small fraction of the price paid for a similar Type A object. Sellers often get away with nondisclosure because Type B treatments are difficult to detect. Testing at a gemological laboratory is often required for detection of Type B treatments.
Type C Jadeite
Type C jadeite usually has all of the treatments of Type B jadeite, but the object has also been dyed to a more desirable color. The dyes can fade over time or with exposure to heat and light. For these reasons, Type C treatments should always be disclosed.
Dye treatment can often be detected by examination with a microscope, spectroscope or gemological filters, but this testing should not be needed – the seller should disclose the full extent of treatment for every object that is sold. Disclosure doesn’t always happen because Type C jadeite sells for a small fraction of similar objects with Type B treatment.
Type C objects should be purchased for a price that assumes temporary use for a few years. Anyone who spends the serious money on jade should know the difference between jadeite and nephrite, have a good knowledge of jadeite treatments, how they impact value, and how they impact future durability and appearance. Confirmation of the jadeite type by a gemological laboratory is a good idea for expensive items. These services are easy to obtain and usually cost a tiny fraction of what is paid for a Type A jadeite item.