Pewter of the Bronze Age in the Near East. The earliest piece of pewter found is from an Egyptian tomb from 1450 BC. The constituents of pewter were first controlled in the 12th century by town guilds in France. By the 15th century, the Worshipful Company of Pewterers controlled pewter constituents in England. This company originally had two grades of pewter, but in the 16th century a third grade was added. The first type, known as "fine metal", was used for tableware. It consisted of tin with as much copper as it could absorb, which is about 1%. The second type,
Structuring element are two main characteristics that are directly related to structuring elements: Structuring elements are particular cases of binary images, usually being small and simple. In mathematical morphology, binary images are subsets of a Euclidean space "R" or the integer grid "Z", for some dimension "d". Here are some examples of widely used structuring elements (denoted by "B"): In the discrete case, a structuring element can also be represented as a set of pixels on a grid, assuming the values 1 (if the pixel belongs to the structuring element) or 0 (otherwise). When used by a hit-or-miss transform, usually the structuring