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The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
The chemical elements were discovered in identified minerals and with the help of the identified elements the mineral crystal structure could be described. One milestone was the discovery of the geometrical law of crystallization by René Just Haüy , a further development of the work by Nicolas Steno and Jean-Baptiste L. Romé de l'Isle (the ...
Candle moulding machine in Indonesia circa 1920. Candle making was developed independently in a number of countries around the world. [1]Candles were primarily made from tallow and beeswax in Europe from the Roman period until the modern era, when spermaceti (from sperm whales) was used in the 18th and 19th centuries, [2] and purified animal fats and paraffin wax since the 19th century. [1]
Vauquelin discovered the oxide in beryl and emerald in 1798, and in 1808 Davy showed that this oxide has a metallic base although he could not isolate it. [ 64 ] [ 106 ] Vauquelin was uncertain about the name to give to the oxide: in 1798 he called it la terre du beril , but the journal editors named it glucine after the sweet taste of ...
Wax candle. Waxes such as paraffin wax or beeswax, and hard fats such as tallow are used to make candles, used for lighting and decoration. Another fuel type used in candle manufacturing includes soy. Soy wax is made by the hydrogenation process using soybean oil.
Metallurgy derives from the Ancient Greek μεταλλουργός, metallourgós, "worker in metal", from μέταλλον, métallon, "mine, metal" + ἔργον, érgon, "work" The word was originally an alchemist's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia ...
These rays, which he discovered but were later called cathode rays by Eugen Goldstein, produced a fluorescence when they hit a tube's glass walls and, when interrupted by a solid object, cast a shadow. 1869: William Crookes: Invented the Crookes tube. 1873: Willoughby Smith: Discovered the photoelectric effect in metals not in solution (i.e ...
Robert Augustus Chesebrough (/ ˈ tʃ iː z b r oʊ /; [1] January 9, 1837 – September 8, 1933) was an American chemist who discovered petroleum jelly—which he marketed as Vaseline—and founder of the Chesebrough Manufacturing Company.