Necklaces have been an integral part of jewelry since the time of ancient civilizations and pre-date the invention of writing. The birth of necklaces is believed to be as old as the Stone Age, which is around 40,000 years old. The oldest necklaces were made of purely natural materials - before weaving and the invention of string, durable vines or pieces of animal sinew left over from hunts were tied together and adorned with shells, bones or teeth or colorful skins of human prey animals, bird feathers, corals, carved pieces of wood, colorful seeds or stones or naturally occurring gems, or other beautiful or artful natural elements found nearby. Cloth working and metalworking greatly expanded the range of jewelry available to humans. Twine and string enabled the development of smaller, more durable, more intricate necklaces. After the Bronze Age began and humans discovered how to melt metal and cast it into shapes, bronze, copper, silver, gold, electrum, platinum and a variety of other metals were used to make eye-catching necklaces for both men and women, and metal chains became possible. Gem cutting and glassblowing allowed faceted and highly polished gemstones and/or beautiful art glass to be added to pieces. In the modern era, a variety of new metals are available for necklaces that earlier generations could not properly melt until high-temperature crucibles and blowtorches were developed, such as stainless steel and titanium; electroplating has enabled mass ownership of gold (or at least gold-veneer) jewelry. Miniaturisation and laser etching enable the crafting of finely detailed artwork, or insignias or other calligraphy, within individual necklace elements.
A necklace is an article of jewellery which is worn around the neck. Necklaces are frequently formed from a metal jewellery chain. Others are woven or manufactured from cloth using string or twine. Common features of necklaces include features such as colorful stones (particularly gemstones or jewels), wood (usually carved or polished), art glass, feathers, shells, beads or corals - a wide, wide variety of other adornments have also been used. If a necklace includes a primary hanging feature, it is called a pendant; if the pendant is itself a small container, that is called a locket.