Mirrors
We use mirrors in our daily lives. They are quite useful especially when it comes to using them on cars and in the morning before work to make sure we don't have bad hair days.
Some Interesting History On The Mirror
Ancient times
The first mirror used was probably dark stone bowls or wooden buckets of water held very still. Other early examples of mirrors were pieces of polished obsidian stone or flattened copper.
Early Middle Ages
By this time a lot of cultures were using discs of polished metals such as copper, bronze or silver. During Roman empire times the servants used polished silver as mirrors. Speculum mirrors were made of copper and tin, they originated in China and India. These mirrors were hard to make therefore only the wealthy could afford them.
A Greek philosopher, Socrates, would tell young people to use mirrors so that they would value their beauty if they were good looking and hide their ugliness if they were not.
The first glass mirrors were made with soda-lime glass and glass blowing. They would blow cylindrical glass tubes and cut them into rectangles. They then covered the glass in lead or gold leaf at the back. But due to the high costs and poor quality, metal mirrors stayed popular. Silver coated metal mirrors were made in China using an amalgam. The amalgam was heated until the mercury boiled away.
The Middle Ages to renaissance
People started to make a break through with glass mirrors at this point. French glass makers started making flat glass plates. Then a better method was developed in Germany and perfected in Venice. The venetian glass makers also started using glass backed with lead. They started being produced in Spain in the 11th century due to their crystal-clear clarity.
During the early European Renaissance, a fire gilding technique was developed to produce a highly reflective, uniform coating for glass mirrors. The back of the glass was coated with a tin-mercury amalgam and then the mercury was evaporated by heating the piece. This process caused less of a thermal shock for glass than the old molten lead method. For a century Venice retained a monopoly on the tin fusing technique. Venetian mirrors were framed to serve as luxurious decorations for palaces everywhere, especially in Europe, and they were very expensive.
For example, at the end of the 17th century It was reported that the Countess of Fiesque had traded an entire wheat farm for one mirror.
At the end of this century, however, the secret was leaked through economic espionage. French workshops were successful on a grand scale Industrialization of the process, eventually making the mirrors affordable for masses, despite the toxicity of the vapor from the mercury.