 In the first part of this class, we've learned about the chemical and physical properties of the oxide minerals that make up the family of minerals known as the ochres or the earth colors and learned about the conditions under which these are formed in the earth and how they come to make themselves available to humans for utilization as pigments in various types of art and expression throughout human history. In the next part, we're going to move on to talking about the expression and the use and symbolism of these colors in art, and we move on to the art history part of the class. So just one of the things we're going to be doing first in this unit, and this is something we're going to do in every unit, is we're going to explore how we get from the rock to the art material. So what I'm holding here is actually something called encaustic. This is pigment suspended in melted wax. Here it has dried, so it's nice and solid. I can pick up a chunk of it. But in the very late Egyptian period and sort of early Roman period, this was one of the primary uses for ochre pigment, creating a special type of mummy portrait that we're going to talk about. We know that the ancient Egyptians used powdered ochre mixed with gum arabic, which is a tree resin coming from the acacia tree in paintings in their tombs. And so they would have crushed it and mixed it up probably with something like this mortar and pestle or with a grinding stone and then mixed it with that liquid with gum arabic dissolved in water and then used that to paint on walls. Powdered ochre, as Maureen also mentioned, could be used kind of like a crayon. And we know that artists in the Renaissance would actually use powdered ochre, like what we have in these vials here, in kind of like a fine talcum powder sort of texture. They would stick it into bags and use it to pounce onto a wall in order to transfer a drawing. What they would do for a large wall painting, for example, would be to make a big paper drawing, hang that on the wall, put a bunch of little pinpricks in that drawing and then pounce the powdered pigment up against that in order to transfer that drawing to the wall for a wall painting. And in my studies, I actually visited a museum full of these under drawings. So we're going to explore all of that because it was relatively inexpensive and plentiful. We're not going to have some of the really deep meanings associated with ochre that we're going to have with some of our other materials. But we will explore meaning and especially technique and then look into some case studies.