Making mirrors began with polishing metals for as long and as frequently as the maker was able. These early mirrors didn’t produce the best images, but they were the best people back then could get. Thankfully, in the 17th century, mirror makers learned to back glass with reflective metals like silver, mercury, and aluminum.
As explained in an article for How Products are Made, the principle behind mirrors is quite simple. To compensate for the poor reflectivity of glass, backing it with a highly-reflective material is necessary. All but 4 percent of light passes through the glass, and everything is reflected back by the backing. Often, a protective paint ensures the metal backing’s integrity from behind.
At one point, silver was the most commonly used metal as reflective backing. Molten silver is spread all over the mirror’s backside, resulting in distorted images similar to those created by modern funhouse mirrors. This type of mirror, however, was prone to flaking due to the thin, uneven spreading of silver. These days, a far more advanced technique is used in applying silver backings.
Mercury was also used as backing, but, as many would know, mercury carries some health hazards. While mercury spreads more evenly than silver, resulting in a clearer reflection, sealing the toxic metal was a problem for manufacturers. Some mirrors made after 1940 had aluminum backing. Not only were these safer, they were also less costly to produce due to aluminum’s abundance.
The process of making mirrors for Indianapolis homes and offices can be summarized in two steps: cut and coat. After a slab of glass is cut, the metal backing is applied onto what would be the rear. The backing isn’t applied as a solid sheet but is sprayed evenly as a liquid solution. The mirror slabs are then cured in an oven at 265 OF to 285OF for at least 6 minutes.
At this point, the finished product can be shipped straight to your home or office. If you want a more stylish vanity mirror, however, you can get one from a noted glass company in Indianapolis like Suburban Glass, which does further processing and finishing of mirrors to make them more ornate and decorative. If you want a customized design, you may also bring your own slab to them for processing.
While silver and aluminum mirrors remain the most popular kinds in the market today, major leaps in mirror and glass making ensure that you get accurate and clear reflections as much as possible.
(Source: Mirror, How Products are Made)