Sunday, March 25, 2007

Jewellery and society

Jewellery is factually any piece of fine material used to decorate oneself. Although in earlier times jewellery was created for more convenient uses, such as wealth storage and pinning clothes together, in recent times it has been used almost completely for beautification. The first pieces of jewellery were made from likely materials, such as bone and animal teeth, shell, wood and engraved stone. Jewellery was often made for people of high importance to show their status and, in many cases, they were covered with it.Jewellery is made out of almost every material recognized and has been made to garnish nearly every body part, from hairpins to toe rings and many more types of jewellery. While high-quality and artistic pieces are made with gemstones and valuable metals, less pricey costume jewellery is made from less-valuable materials and is mass-produced.Form and function Kenyan man exhausting tribal beads.Over time, jewellery has been used for a number of reasons: Currency, wealth display and storage, purposeful Symbolism Protection and Artistic display Most cultures have at some point had a practice of observance large amounts of wealth stored in the form of jewellery. Numerous cultures move wedding dowries in the form of jewelry, or create jewelry as a means to store or display coins. on the other hand, jewellery has been used as a currency or trade good; a mostly poignant example being the use of slave beads.

In creating jewellery, a variety of gemstones, coins, or other valuable items can be used, often set into precious metals. Common expensive metals used for modern jewellery include gold, platinum or silver, although alloys of nearly every metal known can be encountered in jewellery -- bronze, for example, was common in Roman times. Most gold jewellery is made of an alloy of gold, the purity of which is affirmed in karats, indicated by a number followed by the letter K. For example, ordinary gold jewellery ranges from 10K (41.7% pure gold) to 22K (91.6% pure gold), while 24K (99.9% pure gold) is considered too soft for jewellery use.
Platinum alloys variety from 900 (90% pure) to 950 (95.0% pure). The silver used in jewellery is usually sterling silver, or 92.5% fine silver.Other generally used materials include glass, such as merged glass or enamel; wood, often carved or turned; shells and other natural animal substances such as bone and ivory; natural clay, polymer clay, and even plastics.

Adult Halloween Costumes

Monday, March 12, 2007

Natural satellite

A natural satellite is a non-man-made object that orbits a planet or other body larger than itself. They are often called moons. The term natural satellite may also refer to a planet orbiting a star, as is the case with planets orbiting the Sun and even the Sun itself as it orbits the galactic center of the Milky Way. There are 240 known moons within the Solar system, including 162 orbiting the planets , 4 orbiting dwarf planets, and dozens more orbiting small solar system bodies. Other stars and their planets also have natural satellites.

The large gas giants have extensive systems of moons, including half a dozen comparable in size to Earth's moon. Of the inner planets, Mercury and Venus have no moons at all; Earth has one large moon ; and Mars has two tiny moons, Phobos and Deimos. Among the dwarf planets, Ceres has no moons, Eris has one, Dysnomia, and Pluto has three known satellites, Nix, Hydra, and a large companion called Charon. Charon is also unusual in that it does not orbit Pluto, but rather both bodies orbit a barycenter in empty space, making Pluto-Charon a binary system.

Adult Halloween Costumes

Thursday, March 01, 2007

Great Pyramid of Giza

Believed by mainstream Egyptologists to have been constructed in approximately 20 years, the estimate accepted in the mainstream for its date of completion is c. 2560 BC. This date is loosely supported by archaeological findings which have yet to reveal a civilization older than the fourth dynasty in the area.

The Great Pyramid is the oldest and largest of the three pyramids in the Giza Necropolis bordering what is now Cairo, Egypt in Africa. It is the main part of a complex setting of buildings that included two mortuary temples in honor of Khufu , three smaller pyramids for Khufu's wives, an even smaller "satellite" pyramid, a raised causeway connecting the two temples, and small mastaba tombs surrounding the pyramid for nobles. One of the small pyramids contains the tomb of queen Hetepheres , sister and wife of Sneferu and the mother of Khufu. There was a town for the workers, including a cemetery, bakeries, a beer factory and a copper smelting complex. More buildings and complexes are being discovered by The Giza Mapping Project.

Adult Halloween Costumes