Ingot in the context of "Forging"

Bullion is non-ferrous metal that has been refined to a high standard of elemental purity. The term is ordinarily applied to bulk metal used in the production of coins and especially to precious metals such as gold and silver. It comes from the Anglo-Norman term for a melting-house where metal was refined, and earlier from French bouillon, "boiling". Although precious metal bullion is no longer used to make coins for general circulation, it continues to be held as an investment with a reputation for stability in periods of economic uncertainty. To assess the purity of gold bullion, the centuries-old technique of fire assay is still employed, together with modern spectroscopic instrumentation, to accurately determine its quality.

Bullion is sometimes contrasted with specie, the latter being coin made of bullion (or synonymously, bullion coin). Thus understood, bullion refers to precious metal kept in forms other than coin, namely bars, ingots, or plates, including regional and historical variants such as grivnas in Eastern Europe or sycees in China.

A gold bar, also known as gold bullion or a gold ingot, is a quantity of refined metallic gold that can be shaped in various forms, produced under standardized conditions of manufacture, labeling, and record-keeping. Larger varieties of gold bars, produced by casting molten metal into molds, are called ingots. Smaller bars are often created through minting or stamping from rolled gold sheets. Central banks typically hold the standard 400-troy-ounce (438.9-ounce; 27.4-pound; 12.4-kilogram) Good Delivery gold bar in their gold reserves and it is widely traded among bullion dealers. Additionally, the kilobar, weighing 1,000 grams (32.15 troy ounces), and the 100-troy-ounce (109.7-ounce; 6.9-pound; 3.1-kilogram) gold bar are popular for trading and investment due to their more manageable size and weight. These bars carry a minimal premium over the spot price of gold, facilitating small transfers between banks and traders. While most kilobars have a flat appearance, a preference for brick-shaped bars exists among some investors, particularly in Europe.

A sycee (/ˈsaɪsiː, saɪˈsiː/; from Cantonese 細絲, Jyutping: Sai3 Si1, lit. 'fine silk') or yuanbao (traditional Chinese: 元寶; simplified Chinese: 元宝; pinyin: yuánbǎo; Jyutping: jyun4 bou2; Pe̍h-ōe-jī: Goân-pó; lit. 'primary treasure') was a type of gold and silver ingot currency used in imperial China from its founding under the Qin dynasty until the fall of the Qing in the 20th century. Sycee were not made by a central bank or mint but by individual goldsmiths or silversmiths for local exchange; consequently, the shape and amount of extra detail on each ingot were highly variable. Square and oval shapes were common, but boat, flower, tortoise and others are known. Their value—like the value of the various silver coins and little pieces of silver in circulation at the end of the Qing dynasty—was determined by experienced moneyhandlers, who estimated the appropriate discount based on the purity of the silver and evaluated the weight in taels and the progressive decimal subdivisions of the tael (mace, candareen, and cash).

In present-day China, gold sycees remain a symbol of wealth and prosperity and are commonly depicted during the Chinese New Year festivities. Paper imitations of gold- or silver-colored sycees are burned along with hell money as a part of Chinese ancestral veneration for Tomb Sweeping Day and the Ghost Festival.

A boule is a single-crystal ingot produced by synthetic means.

A boule of silicon is the starting material for most of the integrated circuits used today. In the semiconductor industry synthetic boules can be made by a number of methods, such as the Bridgman technique and the Czochralski process, which result in a cylindrical rod of material.

The Czochralski method, also Czochralski technique or Czochralski process, is a method of crystal growth used to obtain single crystals (monocrystals) of semiconductors (e.g. silicon, germanium and gallium arsenide), metals (e.g. palladium, platinum, silver, gold), salts and synthetic gemstones. The method is named after Polish scientist Jan Czochralski, who invented the method in 1915 while investigating the crystallization rates of metals. He made this discovery by accident: instead of dipping his pen into his inkwell, he dipped it in molten tin, and drew a tin filament, which later proved to be a single crystal. The process remains economically important, as roughly 90% of all modern-day semiconductor devices use material derived from this method.

The most important application may be the growth of large cylindrical ingots, or boules, of single crystal silicon used in the electronics industry to make semiconductor devices like integrated circuits. Other semiconductors, such as gallium arsenide, can also be grown by this method, although lower defect densities in this case can be obtained using variants of the Bridgman–Stockbarger method. Other semiconductors such as Silicon Carbide are grown using other methods such as physical vapor transport.