October 21, 2013
I was looking up blue pigments and found there are a lot of natural substances that have been used to create blue. I’m not going to go into the different substances just yet because after reading about some of these I wondered what was used in blue tattoos. They (any tattoo) are more popular than ever (makes me wonder if I’m in the minority). It seems that blue ink chemistries can vary and it looks like various forms of heavy metals are used. Cobalt is one pigment in blue tattoos. Cobalt is an element that is gray colored when pure (that’s not how we find it in nature) but in the oxide form it’s blue. Other blue inks in tattoos might have copper or iron oxides. Along with reading about blue ink in tattoos I found that the vehicle used in the injection can increase the systemic absorption of these metals. I believe a waiver is supposed to be signed before getting a tattoo? Good idea.
There are a lot of different things that were used and may still be used to make blue pigments and dye. The plant commonly called woad has leaves that can be boiled and then through certain steps a blue residue will result. Another plant dye, Indigo, also comes from a few different types of plants and was considered a luxury product by Greeks and Romans. These days our blue jeans are dyed with a synthetic indigo but I found there is a brand of denim called Momotaro in Japan that uses natural indigo dyes…and is quite pricey.
Other blue dyes and pigments come from mineral forms like ultramarine and lapis. Ultramarine was given it’s name because it was imported from over seas. Grinding the lapis into a powder and then combining it with another product can make blue paints or printing inks. Ultramarine can be found in cave paintings and Renaissance art and may have been used sparingly in some art because of it’s cost to produce. Synthetic ultramarine (aka, Prussian blue) may be found as a bluing agent in detergents which is interesting. The resultant effect of bluing is to make whites whiter through a subtractive coloring effect with the yellowing that occurs with white clothes. Azurite is another mineral with copper in it that was substituted for ultramarine because of it’s lower cost.
What about ochres? Well, they aren’t blue in color but they were and still are the basis for a lot of paintings. I live by a lot of red rocks in Colorado. That color and the variations of it is due to the iron content that has oxidized….rust basically. Ochre colors can be yellow, orange, red and somewhere in that range and can be found in modern paints and in cave paintings as long as 75,000 years ago.
By no means have I covered or could possibly cover all the blue pigments and dyes, nor the other basics used in making paint colors. But, I will pursue my education further in this area because….I can’t stop reading about all these fascinating things.
And you know why blue is blue, right? Well, if we’re not talking about blue sky and blue eyes and the Tyndall effect or emotion, we’re talking about about the physical effect of how the blue wavelength is reflected off the material. You could say the material isn’t blue, that it only reflects blue wavelengths….but then someone would look at you crazylike.