News From the Oddball Art Laboratory

Breaking EarthPaint News!

Here in the Oddball Art Laboratory, art is also a science, with lots of accidental discoveries. Today's observation is a major breakthrough!

The tool in the bottom left corner of the above photo (also shown below) is my granite mortar and pestle, the most important item in my toolbox.

It is one of the oldest tools in the history of mankind, and it has changed very little over the millennia. I love that it is still in use today, and I often think about its connection to the very first artists, whose work can be seen around the world, in places like the American southwest, or most famously, the caves in Lascaux, France.

I can picture my Paleolithic predecessor using this same tool to grind the rock pigments used to create masterpieces like this one:

To learn more about these amazing Paleolithic artists, visit
The Bradshaw Foundation at www.bradshawfoundation.com

I've had my large granite mortar and pestle for about fourteen years - it's a huge improvement on the tiny, blister-making ceramic one I used when I first began the EarthPaint project. As you can imagine, it has been put to very rough use, crushing every bit of rock paint in my extensive palette.

This is just part of it!


I've worn a deep pocket in the bottom of the mortar (the cup), and the edges of the pestle (the striking stone) have started to chip and wear away. This often results in some of the dark grey granite mixing in with the mineral pigment when I am grinding an especially hard mineral, like the lovely yellow Mookaite Jasper I prepared today. 

I normally use water to separate out some of the granite so the color of the mineral sample isn't affected by the inclusion of dark grey granite. It's a very inefficient process: I usually end up with a fairly clean sample of larger grains, and another mixed color that includes fine particles of both minerals.

Which brings me to today's discovery. After drying out the fresh sample, I compared it to a previous specimen of yellow Mookaite and found it matched perfectly. This is a rarity in itself: even two stones of the same mineral are very seldom the exact same color. 

I combined both samples in a larger container, and when I began to brush out the remaining material from the original container I noticed some material clinging to the bottom, attracted by the magnet I had glued there. It was the granite from the mortar and pestle, which had previously dulled the bright yellow of the Mookaite. The magnet had separated the two mineral samples far more effectively than my water sifting method ever could. 

I quickly placed small magnets in the samples that are still immersed in water: very fine particles can sometimes take days to settle enough to pour off the water and dry the mineral powder. I'll see how well this works to separate out the granite dust from the mineral samples, but I'm excited to learn the granite is magnetically reactive, as this will help me grind pure color samples more easily (except with a few other minerals that I've noticed also have magnetic properties). 

In the meantime, I have completely resurfaced my beloved Stone-Age tool, using a Dremel with a sanding attachment, and a top coat of stone sealer to limit future contamination of my pigments.

Every day I learn something new about minerals, mediums, adhesives or other random tidbits: I love all the little accidental scientific discoveries I make in the Oddball Art Laboratory!

In the above left photo, you can see how this mica sample has been sifted with water to separate fine and coarse grains, as well as a third, darker sample that also includes some of the earth that was mixed in with the mica. The above right specimen is Lapis Lazuli (my favorite), and below is an unidentified orange mineral of local origin - both these minerals will yield a much brighter color when used with a glossy medium, while any mineral with reflective properties like mica will look best if used with certain types of matte-finish mediums, which bring out the sparkle rather than darkening the color. I will elaborate on this in a later post.