Lost-wax castingLost-wax casting - also called investment casting, precision casting, or cire perdue (siʁ pɛʁdy; borrowed from French) - is the process by which a duplicate sculpture (often a metal, such as silver, gold, brass, or bronze) is cast from an original sculpture. Intricate works can be achieved by this method. The oldest known examples of this technique are approximately 6,500-year-old (4550–4450 BC) and attributed to gold artefacts found at Bulgaria's Varna Necropolis.
ChalcolithicThe Chalcolithic (also called the Copper Age and Eneolithic), is an archaeological period characterized by the increasing use of smelted copper. It follows the Neolithic and precedes the Bronze Age. It occurs at different periods in different areas, and is absent in some parts of the world, such as Russia. Stone tools were still predominantly used during this period. The archaeological site of Belovode, on Rudnik mountain in Serbia, has the world's oldest securely dated evidence of copper smelting at high temperature, from 5000 BC (7000 BP).
CopperCopper is a chemical element with the symbol Cu (from cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.
TerracottaTerracotta, also known as terra cotta or terra-cotta (ˌtɛrraˈkɔtta; baked earth; ), is a term used in some contexts for earthenware. That is to say it is a clay-based unglazed or glazed non-vitreous ceramic, fired at relatively low temperatures. Usage and definitions of the term varies, such as: In art, pottery, applied art, craft, construction and architecture, "terracotta" is a term often used for red-coloured earthenware sculptures or functional articles such as flower pots, water and waste water pipes, tableware, roofing tiles and surface embellishment on buildings.
CarnelianCarnelian (also spelled cornelian) is a brownish-red mineral commonly used as a semiprecious stone. Similar to carnelian is sard, which is generally harder and darker; the difference is not rigidly defined, and the two names are often used interchangeably. Both carnelian and sard are varieties of the silica mineral chalcedony colored by impurities of iron oxide. The color can vary greatly, ranging from pale orange to an intense almost-black coloration. Significant localities include Yanacodo (Peru); Ratnapura (Sri Lanka); and Thailand.
JasperJasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. The common red color is due to iron(III) inclusions. Jasper breaks with a smooth surface and is used for ornamentation or as a gemstone. It can be highly polished and is used for items such as vases, seals, and snuff boxes. The specific gravity of jasper is typically 2.5 to 2.9.
Potter's wheelIn pottery, a potter's wheel is a machine used in the shaping (known as throwing) of clay into round ceramic ware. The wheel may also be used during the process of trimming excess clay from leather-hard dried ware that is stiff but malleable, and for applying incised decoration or rings of colour. Use of the potter's wheel became widespread throughout the Old World but was unknown in the Pre-Columbian New World, where pottery was handmade by methods that included coiling and beating.
