REVERSIBLE FILLS FOR TRANSPARENT AND TRANSLUCENT MATERIALS
As previously mentioned, properties of materials vary from country to country. Moreover, since restoration is not normally the prime purpose for which they were intended, materials may be altered by manufacturers without notification. Thus it is important that before work commences experiments be undertaken on materials in use for the first time to confirm that their performance will be as expected. A full discussion of materials used in conservation can be found in Horie (1987).