Color primer, part 1, and osage orange dye recipes

When I asked a few posts ago about topics to write on, I got a couple of great questions relating to why different dyes produce a given color–why osage orange, for instance, gives a yellow, but bloodroot gives a red. The answers to these questions are related to the approach I’m using to identify dyes on quillwork in museum collections, but before jumping straight to the causes of color, I thought it would be useful to post a short-and-sweet explanation on why objects appear colored in the first place–my way of laying the groundwork for what will follow. And since this blog is about early quillwork dyes, I thought it might be interesting to take a look at some of the instructions for dye bath preparations as I come across them. With no further introduction, then:

Why objects are colored

In the simplest sense, objects are colored because of the interaction of light with the object. If you shine a light on an object, that light is either reflected back to you or is absorbed (i.e., not reflected back); if the object is transparent, like a piece of clear glass, some of that light will be transmitted through the object and emerge on the other side. You’ll probably recall that ‘white’ light–whether from standard light bulbs or the sun–is made up of several wavelengths of light, representing the colors red, orange, yellow, green, blue, and violet. How do these two facts contribute to a quill’s color?

Consider the yellow quills in the photo at the top of the last posting. If having to choose between opaque or transparent, we’d easily call these quills opaque because we can’t see through them. Since it’s opaque, a yellow quill has to reflect or absorb light; in this case (as in most), it does both. When white light hits a quill colored with a yellow dye, all wavelengths of light except those corresponding to yellow are absorbed. The yellow wavelengths are reflected back to our eyes, and thus the quill looks yellow.

If you’ve ever worked with stage lighting, you’ll know that light mixes a little differently than, say, paint. While the primary colors of paint (those that can’t be made from mixing other colors) are yellow, blue, and red, the primary colors of light are green, red, and blue. By mixing red and green light, we’ll produce a yellow beam; that beam in turn will be reflected by our dyed quill, and it will still look yellow. But If we mix pure red and pure blue light, the resulting magenta beam will be completely missing the yellow wavelengths. When viewed in this new light, our yellow quill will now appear black.

If this seems a little strange right now, hang in there with me! In the next posting, we’ll turn to some graphics to look at why some dyes are red, some yellow, and how it’s possible to have dyes as chemically different as osage orange, wolf moss, and gold thread give nearly the same color to a quill. In the meantime….

A dye procedure for osage orange

Lynne Richards and Ronald J. Tyrl have written a useful book titled, Dyes from American Native Plants: A Practical Guide. This book doesn’t claim to be a guide to Native American dye technology, but there’s some inevitable overlap in the plants discussed. Nor am I presenting the following procedure for producing a yellow dye bath from osage orange as one that would have been used by any of North America’s Native communities. Nonetheless, I thought it would be interesting to see how a bath could be produced:

According to Richards and Tyrl, a ‘golden yellow’ can be obtained on wool from an osage orange dye bath using the bark of the tree with an alum mordant over heat. For those of you familiar with the Munsell Color System, ‘golden yellow’ is described further as either 2.5Y 8/8 or 2.5Y 8/10. A ‘bright yellow,’ 5Y 8.5/14 or 7.5Y 8/12, can be obtained from a bath prepared using the leaves (still mordanted with alum).

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