An alloy of copper and tin, sometimes containing small proportions of other elements such as zinc or phosphorus. It is stronger, harder, and more durable than brass, and has been used extensively since antiquity for cast sculpture. When used correctly, it will "replicate a three-dimensional model with such exactness that details as subtle as the artist&#39;s fingerprints can be reproduced." (Conner, 157) During the 19th century in Europe and America, bronze and marble were equally popular in sculpture, but bronze took precedence in the 20th century because it required less hard labor for the sculptor, did not require a huge staff of artisans, was more durable when finished, and could be reproduced without much additional attention from the sculptor. Bronze alloys vary in color from a silvery hue to a rich, coppery red. Today U.S. standard bronze is composed of 90% copper, 7% tin, and 3% zinc. From 1800 BC bronze has been one of the more useful materials to humanity. The Egyptians, Greeks and Persians used it extensively, and Florence, Italy under the rule of the Medici family, became a center for bronze casting. The name is likely derived from the Italian word "bruno" or brown. The earliest casting method for bronze was pouring the hot liquid into a design cut in stone. Sand molds were used for simple objects, and the Greeks pioneered methods of making large pieces repeatedly from an original model. In the 19th century, a method of bronze electrotyping was devised for making exact copies of antique and others sculptures. Bronze foundries were set up at Naples for making reproductions of statuary excavated at Pompeii, and the copies became popular items in Victorian-style homes in the late 19th century. In Paris, methods were developed for adding color to bronze, which unaltered had a golden-brown coloration that eventually became dark. Additional zinc added golden tones; lead added a blue-grey tint; tin and silver in high content imparted a black patina; and mercury was used for gilding, but that process proved poisonous. Unearthed bronzes vary in coloration depending upon the composition of the soil, and ones found underwater have an olive-green color and hard surface if they have been submerged for long periods. American sculptors known for work in bronze include Frederick Remington, Charles Russell, David Smith, William Zorach, Harriet Frishmuth, Glenna Goodacre, Augustus Saint-Gaudens, Paul Manship, James Earle Fraser and Daniel Chester French. Sources: Greta Elena Couper, "An American Sculptor on the Grand Tour"; Janis Conner and Thayer Tolles, &#39;Double Take&#39;, "The Magazine Antiques", November 2006. <br><br>An alloy of copper and tin, sometimes containing small amounts of other elements in varying proportions such as zinc and phosphorus. Harder and more durable than brass and used extensively since antiquity for casting sculpture. Bronze alloys vary in colour from silvery hues to rich, coppery red. Different countries have different standards for the mix - and mixes also may vary from one foundry to another. In its molten form, bronze is poured into the main channel or sprue of an investment casing surrounding a sculpture to produce the final cast piece of artwork.