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The first mirrors used by people, most likely, were ponds with dark and calm water, or water collected in vessels of a certain type. The first mirrors produced were pieces of polished volcanic glass (obsidian). Samples of obsidian mirrors were discovered on the territory of modern Turkey and are dated about 6000 BC. Polished stone mirrors from Central and South America are approximately dated 2000 BC. Polished copper mirrors of 4000 BC were found in Mesopotamia and 3000 BC in Ancient Egypt. In China, bronze mirrors have been manufactured since about 2000 BC. Mirrors from other metal alloys, such as mirror bronze, could be produced in China and India. Mirrors made of mirror copper or other precious metals were difficult to manufacture and belonged only to wealthy people.
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It is believed that a glass mirror with a metal coating was invented in Sidon (modern Lebanon) in the first century AD. A glass mirror covered with gold leaf was mentioned by the Roman author Pliny in his Natural History, written around 77 AD. The Romans also developed a technology for producing a coarse mirror by coating blown glass with molten lead.
Parabolic
mirrors were described and studied in Ancient Greece by mathematician Diocles in his work “On Burning Mirrors”. Ptolemy conducted several experiments with curved iron mirrors and discussed flat, convex spherical and concave spherical mirrors in his work Optics. Parabolic mirrors were also described by physicist Ibn Sahl in the 10th century. At the same time, Ibn Al Khaitam studied convex and concave mirrors of spherical and cylindrical shapes, performed a series of experiments with mirrors and solved the problem of finding a point of a concave mirror, from which the ray will be reflected at another point. By the 11th century, glass mirrors began to be produced in Moorish Spain.
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In China, people began
producing mirrors using silver-mercury amalgam in 500 AD. During the early Renaissance, European manufacturers created an excellent technique for coating glass with a tin-mercury amalgam. The exact date and place of this discovery is unknown, but in the 16th century, Venice - a city famous for its glass processing technology - became the center for the production of mirrors using this new technology. Glass mirrors of this time were a very expensive luxury. An important manufacturer of mirrors was the Sant Gobain factory, created on the initiative of the royal family in France. Bohemian and German mirror manufacturers, usually cheaper, were also known in those days.
It is believed that the invention of a silver-coated mirror was made by the German chemist Justus von Liebig in 1835. Its process consisted in coating a glass with a thin layer of metallic silver by chemical reduction of silver nitrate. This process has been adapted for mass production and has led to increased availability of mirrors at affordable prices. Today, mirrors are typically produced by vacuum deposition of aluminum (or sometimes silver) directly onto a glass surface.
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