Copper Chlorophyllin extract is a concentrated natural green dye obtained from alfalfa, stinging nettles or from other edible plants. Copper is added to make the extracted chlorophyll a more vibrant green. See this article about it’s molecular structure. And this article about why it is even used as a dietary supplement!

This extract can be used to dye any fiber previously mordanted with alum and cream of tartar or gallnuts or aluminium acetate for cellulose fibers.   Different shades of natural green can be obtained depending on the formula and the mordant used.

Chlorophyllin can also be used in liquid paints, watercolors, inks, binders and soaps. 

Chlorophyll is the main photosynthetic pigment of plants. It is present in most of plants and in certain bacteria and algaes.  It is able to capture light energy and convert it into biochemical energy, essential for life.

Chemically, chlorophyllin (an essential molecule for plants) is very similar to hemoglobin (essential molecule of animals).

I have found the Copper Chlorophyllin wool yarns that I have dyed with alum to have relatively good lightfastness in a sunny window, and they exhibited no change in color after a good period of time in a south facing window. 

This is a very potent extract, and I would recommend starting with less and adding more.  When I dyed wool yarn for the first time, I used the recommended amount of almost an ounce in my dye pot.  I did get a deep green, but dyeing it so concentrated all at once, made the yarn a little more coarse and the results less even.  So, I recommend starting with a couple teaspoonfuls depending on the amount of fiber you are planning on dyeing and layering the color if you want a darker green. 

After I dyed the first very dark greens in the first very concentrated bath, all subsequent baths came out pretty much the same nice, warm green, until the dye bath was pretty much exhausted and all those yarns retained a nice soft hand to the fiber. 

Cream of tartar is nice to add at 1 teaspoon per skein and it helps retain the softness of the fiber, which is something that I needed when using copper chlorophyllin.

What I like most about this natural dye, is that it gives you a warmer, blue-toned green than most of the plant dyes that I’ve dyed with to achieve green.  Most plant dyes give a yellow toned green or olive green, and it is hard to naturally dye a more warm tone of green like an emerald green without going to the hassle of overdyeing with indigo.  So, copper chlorophyllin is just an easy way to dye a blue-ish green or grass green without having to over-dye with indigo or Saxon Blue.