While the green earth I collected from Sebright was a nice colour once ground, I have been curious what effect a couple of different experiments might have upon it. What you see in the above photograph is the two extremes I ended up with. The colour of the pigment when ground up originally is roughly in the middle of these two.
On the left is the green I created by putting the green earth into an acid, removing all the limestone impurities. It is a very cool green and I like this colour a lot.
On the right is the green I created by decanting the pigment after mixing it in water and then counting to ten (which allowed some heavy foreign matter to settle). This colour I am really pleased with. It is a warm green and very alive. It is also almost exactly the same shade as the Cyrus green earth I have in my pigment collection.
I always find it interesting when a raw pigment source is refined a bit. Sometimes it has little effect, but, as in this case, sometimes it proves to be the final tweak a colour needs to be really spectacular!