Inlay or overlay

Inlay or overlay They can be applied to plastic fabricating processes such as moldings during or after molding. 

For several centuries mother-of-pearl has been used as an inlay material. This was particularly popular in the Far East, where items of lacquer or tortoiseshell, as well as wood, were inlayed with mother-of-pearl, often using nautilus shell. In India mother-of-pearl has been used as inlay on large pieces of wooden furniture and caskets, and as an overlay on brass items such as jugs and basins. 

Various procedures have been developed for determining the required thickness of the strengthening asphalt layer (overlay or inlay). All can be classified into either deflection procedure or effective thickness procedure. 

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