Mat (picture framing)

In the picture framing industry, a mat (or mount in British English) is a thin, flat piece of paper-based material included within a picture frame, which serves as additional decoration and to perform several other, more practical functions, such as separating the art from the glass. Putting mats in a frame is called matting, a term which can also usually be used interchangeably with mat.

The picture-framing mat is most commonly known by laymen for its use as additional decoration to enhance the look of a framed piece, sometimes in conjunction with a fillet or more rarely, liners made of wooden moulding with a cloth surface. Although matting usually contains only one opening per layer, it may contain none if a picture is "float-mounted" or "top-mounted" (placed on top of the mat), and mats with two or more exist, more commonly with photography of the family or pictures of individual family members type than other types of artwork. Typically the mat or mats, if matched carefully and properly proportioned, serve to help draw the eye in towards the framed piece, or towards a particular key element of the piece. However, while the mat is usually regarded as something to complement or set off the artwork to best effect, or not to interfere or compete with it (neutral-colored mats are often preferred by high-end art galleries), there are some examples of the mat being regarded by the artist as a part of the artwork. Mats can be decorated as described below, used as a surface for the continuation of the artwork within, or can incorporate three-dimensional aspects, though the last two are highly unusual.

Mats are fairly adaptable in the visual sense. Since they are typically quite thin (American-made mats are usually 1/16 of an inch thick, for example), they are able to be cut to "stack" inside of a display, allowing for double, triple or quadruple matting, or even allowing for a fillet in between mats. Mats are available in numerous colors and shades and, less commonly, in preprinted patterns or designs. Mats can easily be found or altered to include further decorative features, such as a cloth covering (most commonly linen or silk, though mats with leather coverings or various other types of cloth covering are also available from some companies) or other decorative coverings or coatings (such as metallic coatings, or textured and patterned coatings that can include rice paper).

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