Assaying is the estimation of the amount of pure metal, and especially of the precious metals, in an ore or alloy. In the case of silver the assay is either by the dry or by the wet process. The dry process is called eupellation from the use of a small and very porous cup, called a cupel, which is usually made of well-burned and finely-ground bone-ash or of magnesia. The cupel, being thoroughly dried, is placed in a fire-clay oven about the size of a drain-tile, with a flat sole and arched roof, and with slits at the sides to admit air. This oven, called a muffle, is set in a furnace, and when it is at a red heat the assay, consisting of a small weighed portion of the alloy wrapped in sheet-lead, is laid upon the cupel. The heat causes the lead to volatilize or combine with the other metals, and to sink with them into the cupel, leaving a bright globule of pure metallic silver, which gives the amount of silver in the alloy operated on. In the wet process the alloy is dissolved in nitric acid, and to the solution are added measured quantities of a solution of common salt of known strength, which precipitates chloride of silver. The operation is concluded when no further precipitate is obtained on the addition of the salt solution, and the quantity of silver is calculated from the amount of salt solution used.
An alloy of gold is first cupelled with lead as above, with the addition of three parts of silver for every one of gold. After the cupellation is finished the alloy of gold and silver is beaten and rolled out into a thin plate, which is curled up by the fingers into a little spiral or cornet. This is put into a flask with nitric acid, which dissolves away the silver and leaves the cornet dark and brittle. After washing with water the cornet is boiled with stronger nitric acid to remove the last traces of silver, well washed, and then allowed to drop into a small crucible, in which it is heated, and then it is weighed. The assay of gold, therefore, consists of two parts: cupellation, by which inferior metals (except silver) are removed; and quartation, by which the added silver and any silver originally present are got rid of. The quantity of silver added has to be regulated to about three times that of the gold. If it be more the cornet breaks up, if it be less the gold protects small quantities of the silver from the action of the acid. Where, as in some gold manufactured articles, these methods of assay cannot be applied, a streak is drawn With the article upon a touchstone consisting of coarse-grained Lydian quartz saturated with bituminous matter, or of black basalt. The practised assayer will detect approximately the richness of the gold from the colour of the streak, which may be further subjected to an acid test. The Goldsmith's Company of London is the statutory assay-master of all England. Research Assaying
Christian Rudolph De Wet was a Boer soldier and politician. He was born in 1854 in the Orange Free State and died in 1922. His father removing into the Transvaal, he fought as a field-cornet at Majuba. Aa member of the Volksraad from 1889 to 1897 he helped to draw the two Dutch Republics together, and in the South African War commanded first in Natal, and then in the west under Cronje, whose rescue at Paardeberg he attempted, but unsuccessfully. After March, 1900, he distinguished himself by his attacks on the British lines of communication, and by his skill in evading capture. He became Commander-in-Chief of the Free State forces, and was the only undefeated Boer general at the end of the war, after which he, with Louis Botha and Delarey, came to Europe to collect funds for his countrymen. He published an account of the struggle in The Three Years' War. In 1907 he became Minister of Agriculture in the Orange River Colony. In 1914 he joined the Afrikaner insurrection, was captured and sentenced to imprisonment for six years, but was released in 1915. Research Christian De Wet
George Bryan Brummell (Beau Brummell) was an English playboy and expert on etiquette and fashion. He was born in 1778 at London and died in 1840. He was educated at Eton and at Oxford, and at the age of sixteen made the acquaintance of the Prince of Wales, afterwards George IV, who made him a cornet in his own regiment of the 10th Hussars, and secured his rapid promotion. The death of his father in 1794 brought him a fortune which he squandered on sumptuous living over a twenty-one year period. His creditors at length became clamorous, and in 1816 he took refuge in Calais, where he resided for many years, partly supported by the remains of his own fortune and partly by remittances from friends in England. Subsequently in 1830 he was appointed consul at Caen, but on the abolition of the post was reduced to absolute poverty, and died in a lunatic asylum at Caen in 1840. Research George Brummell
Daniel Louis Armstrong was a black American jazz musician and singer. He was born in 1900 and died in 1971. He was particularly renowned for his trumpet playing. He first learned to play the cornet in a waifs home in New Orleans, before switching to the trumpet and playing first on Mississippi river boats before forming his own small bands with whom he made some sixty recordings in the 1920s, before leading big bands and appearing in films, including the 1941 'The Birth of the Blues' which had a major influence on Dixieland jazz. Research Louis Armstrong
Louis Botha was a Boer statesman. He was born in 1863 at Greytown, Natal and died in 1919. In his earlier days he took part with the Boers who seized a portion of the territory of the Zulus afterwards incorporated in the Transvaal, and subsequently was cornet in the Vryheid district, and a member of the Transvaal Volksraad. On the outbreak of the South African War he took an active part in the invasion of Natal and the operations against Ladysmith. In 1910 upon the formation of the Union of South Africa he became Prime Minister and Minister of Native Affairs, a post he held until his death. Research Louis Botha
Nat Adderley (Nathaniel Adderley) was an American musician. He was born in 1932 at Tampa, Florida and died in 2000 of diabetes. A popular jazz musician, he is best known as a cornet player playing with various bands, including the Lionel Hampton band from 1954 to 1955. Research Nat Adderley
Sir Ralph Abercromby was a Scottish general. He was born in 1734 at Menstrie, Clackmannshire and died in 1801. He entered the army in 1756 as cornet in the 3rd Dragoon Guards and eventually rose to the rank of major-general in 1787. After serving in Europe during the Seven Years War from 1756 to 1763 he was member of parliament for Clackmannshire from 1774 to 1780 before rejoining the army in 1793 leading successful operations against the French in St Lucia and Trinidad between 1795 and 1796. He was fatally wounded while leading the Anglo-Turk forces against the French at Aboukir Bay in 1801. Research Ralph Abercromby
Cornetite is a rare, brittle, secondary mineral with a chemical composition similar to turquoise. Cornetite is formed in the weatheredoxidation zones of copper sulphide ore bodies and is found in association with brochantite, chrysocolla, liberthenite, limonite, malachite and pseudomalachite. Cornetite was first discovered in 1912 and was confirmed as a distinct mineral in 1917, subsequently being named after the Belgian geologist Jules Cornet. Cornetite is a naturally occurring hydrous phosphate of copper, as is also turquoise. Research Cornetite
The hennin was a cornet head-dress in the form of an elongated cone hung with elaborately arranged veils and worn by women in 15th century England. Research Hennin
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