What color is a mirror? A simple question. One you may never have thought about before, but it certainly gets you thinking. Read on to discover the answer – it just may surprise you.
Is a Mirror All the Colors in the World?
Your first instinct, when asked what color a mirror is, may be to answer with ”all colors”. You may think this because a mirror reflects back every color you could possibly place in front of it, but as far as an answer to this complex question goes, a mirror is not every color.
A mirror is an object with its own identity. Don’t mistake the reflection it makes as the color of the mirror itself. It is just like how an actor can perform on a stage as any number of different characters, but in real life they are still their own unique individual person. A mirror on its own, once you look past the reflection, has its own set of identifying properties. This includes its color. To unravel the mystery of a mirror’s color, we need to start with the construction of a mirror.
Is Green the Big Surprise?
Your common household mirror will more than likely have a flat, uniform surface. This is most often glass. If so, the glass used is what they call float glass. This type of glass is very common and found in many products other than mirrors such as window panes. The float glass commonly used when making a mirror is made with soda-lime. This gives the glass a subtle green tint.
To prove that a mirror is green, place two mirrors so that they are in front of each other. That image you see, which looks like it stretches to infinity, is what they call an endless reflection. If you look closely, you will see that way back in this reflection, where the image turns into a small speck of black, there will be a green color. You are seeing the actual color of the glass at this point. That is why many people will tell you that a mirror is actually green.
In 2004, Raymond L. Lee and Javier Hernandez-Andres produced a research paper where they talked about visiting Grenada, Spain’s Science Museum, to measure the images created when mirrors are placed in front of one another, to make those tunnel images that seemingly stretch on forever. Their findings back up the idea that a mirror is actually green. They found that mirrors will reflect light best at wavelengths of 495 to 570 nanometers. This range is what our human eye sees as the color green.
Maybe Silver is the Answer?
Maybe you think mirrors are silver. After all, the illustrations of mirrors in the fairytale books are always silver. You may have also noticed that images of mirrors in online and print ads are often silver. If you look in your own mirror, trying to search for one distinct color, you will probably come up with silver as well. You can also come to this conclusion if you look at a mirror that has a crack in it or look across the mirror at an angle. You will see silver in these circumstances. So, it is easy to have the impression that a mirror is silver. Just like green, this conclusion is also based on how a mirror is made.
Behind the float glass, mirrors are made with either polished aluminum or silver which is used as the actual reflective surface. Some might even include a coating of mercury in a technique referred to as mercury silvering. Liquid mirrors used in the early 19th century for telescopes used liquid mercury or gallium to create a continuously moving reflective layer. Liquid mirrors are still used in space observatories today, but the mirrors you have in your home or car typically use aluminum as their reflective surface.
So if you say that a mirror is silver, you are right. Break down a mirror into its basic components and you find a highly polished metal surface that has a silver hue placed under a piece of float glass with a frame to hold it all together. You will see this silvery layer if the mirror cracks or you look at it from just the right angle. Hence, the answer of silver as the color of a mirror is not incorrect.
What About White?
You may have thought mirrors are white. If so, you aren’t exactly wrong. You are correct in the fact that white is the one color that reflects all of the visible wavelengths of the color spectrum, but if mirrors are white, why can’t you see yourself in all white surfaces? The answer is simple. Most surfaces, such as a white piece of paper or a plain white wall, scatter the light they reflect off in several different directions. A mirror will reflect the light back at you all in the same direction for which it came from. Phil Plait from The Bad Astronomer fame describes mirrors as being a ”smart kind of white.”
The Surprising Answer
So what color is a mirror? It is simple. Your basic household mirror that you will find in your bathroom or bedroom is green-tinged glass over a silver reflective surface that mimics the properties of the color white. Put all of these components together and you have a beautiful and functional mirror that is capable of reflecting all of the colors in the world.