A peak at the process
On this page you can follow along to see raw materials gathered from the natural source and processed into clay or glaze.
Clay straight from the source
This section will cover how to identify and harvest your own clay to throw with. The clay you see harvested here was from an alluvial deposit, but you can also find clay in marine, lacustrine, or primary deposits. Clay is almost never found in a wet and plastic state, so you can identify it in the wild if it dries in nodules that easily break apart or in crackled fragments on the ground.
Clay sourcing and collection
This is what the clay looks like straight from the source at an alluvial deposit. You take chunks of clay (thanking the earth, of course), that seem as a uncontaminated as possible, for processing. Do some geographical research of your surrounding environment to see what minerals your sediments are made up of and where the nearest alluvial, primary, marine or lacutrine deposits are near you. Starting near water is always a solid bet!
Processing the raw material
Do the 'field plasticity test' by rolling out a coil of the clay to see if it is plastic enough to throw with. Add water to the clay and then mix with a drill and metal glaze mixing head until it becomes a slip. Sieve in a 60 mesh sieve if there are many impurities (rock, animal debris, plants, etc).
Applying slip to plaster
Apply the mixed slip (it should be the consistency of yogurt) to the plaster and wait until it dries and becomes clay that you can easily wedge. Flip onto the other side so the consistency remains the same throughout the mixture.
Wedging & Throwing
Once the mixture becomes dry enough that you can wedge it into a ball that does not stick to canvas or plaster, you can then throw with it!
Lastly, fire the pot to see what elements are in the clay body. Start at a low temperature, maybe cone 5 or 6 and see how it holds up. If it does well and doesn't crack or explode, you can then test it with gradually higher temperatures. Start with very small pieces until you know the clay is stable enough to survive a firing.
Sourcing the material
For any glaze you will need silica, alumina and a flux. Silica and alumina can be found naturally in pretty much any rock, which you can grind to dust and hydrate to create a slip, or from a natural clay body. A flux can be sourced from any plant, in this case I used reeds. The silica and alumina source I used was a clay body I re-hydrated from a dried up river bed. You can tell if something is clay if it easily crumbles into nodular pieces or if it appears in crackled fragments on the ground. It will usually have a slightly different color than surrounding sediments, which you can see on the third picture to the right.
Burning the ashes & preparing your base
Next you need to burn the plant material you sourced to collect the ashes for your flux. Additionally, you must sieve & re-hydrate the clay/rock source you collected. If you are just testing the effects of your ash flux, you can mix the ashes into a steady, pre-made base glaze. Sieve the clay/rock source through a 60 mesh sieve until you have discarded all the impurities and are left with a slip.
Dry sieving the ashes (flux) and mixing with the base glaze or slip (the material that contains silica and alumina).
Next you need to dry sieve the ashes and then grind them. I believe it is better to dry sieve (wearing a respirator) because if you were to wash the ashes, it would diminish the flux properties. Next add varying levels of the flux to your slip and make glaze tests. Be sure to only coat the inside of the test pots so it does not run onto any kiln shelves.
Test & adjust ingredients
Once you've finished mixing the two solutions, apply them to your pots for firing and you're done! Once you have tested your glazes, hopefully there is a test that you are happy with and can either make more of or tweak to your preference, adding either more flux or the base slip/glaze.