Finally get to see the bottom of the kiln wall

Just a quick update on last Saturday (1/10/2016) where we finally got our first sight of the bottom of the kiln.

Thanks to the help of our architect, we managed to work undercover in the rain.

We reached the side of the kiln last week by removing the red pottery/kiln material layer (context 52), with context 53 (dark grey clay with charcoal) touching the side of the kiln. Interesting to note all the charcoal/burning as if this surface was exposed during the firing of the kiln.  The layer above this (52) 'peeled off' as if it had been a flat surface.

So this week a small, and I mean small, section was cut into context 53 to expose context 54, which we suspect is the underlaying natural clay to expose the bottom edge of the kiln wall.

There were no further layers showing for the couple of inches we went down.

So the sequence of events in the current ‘theory’ would be:

1. The natural clay (Context 54) was leveled in preparation for the building of the kiln. There is still the possibility that a pit could have been dug, and the kiln built into that, time will tell.
   
2. I only had a peek, but it is possible that there is a thin layer of crushed kiln material at the base (or it may just have been a different colour as it had just been exposed).
   
3. The kiln was built up, and when fired, hardened the natural clay (Context 54) underneath. Context 54 was firm next to the kiln, but not fired.
   
4. During the firing of the kiln a grey clay layer 2cm deep built up with black flecks of charcoal or burning evident.  This could have just been muddy conditions with charcoal settling onto it.  No pot has been found in this layer.
   
5. At some point, a wedge of kiln wall material and pot sherds (Context 52) built up against the side of the kiln.  This is creating the slope that we see in later layers and stops about 1m from the kiln.
   
6. After the kiln went out of use, a dark layer filled with pot sherds (Context 43) was laid over the kiln and at least 2m to 3m around it on the south side.  This could have come from the cutting of the boundary ditch, but the vast quantity of material in this layer offers up the possibility that it was part of the decommissioning of the kiln when it went out of use with the site being leveled.  The black could be a soil layer that built up between the pot sherds between the kiln going out of use and the cutting of the ditch.
   
7. The white clay (Context 12) and the red clay (Context 8) layers were created when the ditch was cut.

    The simple sequence above suggests to me that the kiln may have only been fired for one season, to service a single contract (eg. The building of a single castle). Maybe there are kilns that are in regular use for local demand, and then every few years they get a big ‘sale’ and have to up production for a short period by creating an extra kiln.

I have a 3D model of the section to play with so we can profile exactly the shape of the kiln wall.