<P> Sheet metal is metal formed by an industrial process into thin, flat pieces . It is one of the fundamental forms used in metalworking and it can be cut and bent into a variety of shapes . Countless everyday objects are fabricated from sheet metal . Thicknesses can vary significantly; extremely thin sheets are considered foil or leaf, and pieces thicker than 6 mm (0.25 in) are considered plate . </P> <P> Sheet metal is available in flat pieces or coiled strips . The coils are formed by running a continuous sheet of metal through a roll slitter . </P> <P> In most of the world, sheet metal thickness is consistently specified in millimeters . In the US, the thickness of sheet metal is commonly specified by a traditional, non-linear measure known as its gauge . The larger the gauge number, the thinner the metal . Commonly used steel sheet metal ranges from 30 gauge to about 7 gauge . Gauge differs between ferrous (iron based) metals and nonferrous metals such as aluminum or copper; copper thickness, for example is measured in ounces, which represents the weight of copper contained in an area of one square foot . </P> <P> There are many different metals that can be made into sheet metal, such as aluminium, brass, copper, steel, tin, nickel and titanium . For decorative uses, important sheet metals include silver, gold, and platinum (platinum sheet metal is also utilized as a catalyst .) </P>

How is the thickness of sheet metal measured
find me the text answering this question