ttps:////»https://www.w3.org/TR/REC-html40/loose.dtd»>
The first surfaces capable of reflecting images began to be made around 5,000 years ago in ancient Sumeria – a region in present-day Iraq, encompassing areas close to the city of Baghdad. Mirrors of that time did not produce sharp images, as they were sand-polished bronze plates. In antiquity, these metal instruments reached the hands of the Greeks and Romans and from there they spread across Europe until they became known throughout the continent at the end of the Middle Ages. “Until around the 13th century, mirrors were made of polished metal, silver or bronze alloys hard enough to withstand the mechanical polishing process and not scratch easily”, says engineer Hélio Goldenstein, from USP. The first glass mirrors would only appear in the early 14th century, created by craftsmen from Venice, Italy, who developed a mixture of tin and mercury that, applied to flat glass, formed a thin reflective layer.
Venetian mirrors were famous for their quality and their manufacturing method was kept secret. But, in addition to the high cost, production caused problems for artisans, who were contaminated with mercury, a highly polluting material. “Only in the 19th century were ways discovered to mirror glass with chemical silver, without the need for mercury”, says Hélio. The new technique, safer, simpler and cheaper, popularized mirrors around the world.