When the sun sinks beneath the horizon and the sky begins to fade into darkness, what color would you use to describe the sky? Blue? Purple?
I’m sure there is vast array of colors that people might use to describe the darkening sky: perhaps one could say the sky is blue-violet while another argues that it is blueish-black, yet another may simply say the sky is blue.
There is no right or wrong answer, as colors are perceived differently from person to person, and furthermore, the hue, value, and saturation of the colors in a sunset are somewhat subjective. The reason I asked this question is to highlight the fact that we often use some combination of blue and purple to describe this “gap” in our color spectrum when we have a word for this gap: indigo.
Interestingly, the subject of this post really only applies to English, as our disputes about the definitions of colors has more to do with the language we speak than it does with the colors themselves. Each language — and speaker for that matter — somewhat determines for itself which hues fit into which color category, and some languages even have more names for colors than others, yet these linguistic complications do not actually alter the visible spectrum.
To simplify things, let’s assume that indigo is any wavelength between 450 and 420 nm. This would mean that indigo ranges from a bluish-purple to a purply-blue. The following image shows the spectrum of colors that is often considered to be indigo.
Without the vital component that is indigo, you couldn’t have a rainbow, because a rainbow’s colors are abbreviated as ROYGBIV (Red, Orange, Yellow, Green, Blue, Indigo, Violet), however, as this post suggest, indigo is being forgotten and some people say that a rainbow is only ROYGBV.
What about jeans? People sometimes call them blue jeans, but did you know that the dye used to make denim is technically called indigo dye? Furthermore, the first indigo dye was made from a plant known as Indigofera Tinctoria, whose common name is True Indigo. So why don’t we say indigo jeans?
What are your thoughts on indigo?
Onward American 