So, an explanation about the illustration at the top of this blog. That is a bronze pestle, cast at Kentwell hall into a clay mould. The mould was made of clay, horse dung and sand, mixed together and formed around a wooden patron (a version of the finished object).
Unfortunately the end result was a little squint, due to the mould not keeping it’s proper shape when the patron was taken out. Nevertheless, it illustrates things very nicely. You have the red bloom of copper oxide halfway along, and to the right a head of metal for filling the void. It filled it well too, it wa s a good casting. Importantly you can clearly see the red, oxidised outer layer of clay, which is that colour from the oxidising atmosphere in the furnace when it was fired before the casting, and the inside is black, the colour due to reduction, i.e. not getting enough oxygen in the furnace. You see this on medieval pottery and debris from casting all the time, the red outer from iron oxide in the clay and the black inner where there wasn’t enough oxygen. It helps you piece together the moulds after they have been in the ground for centuries.
I’m going to be commenting a lot about the surface finish of the pieces as well. I suspect I’ll need to get a lathe to get anything like a historic surface finish, because in my experiences so far it has proven impossible to get a finish as good as the medieval artefacts I have examined. Some of that might be done to not casting in stone yet, but that is another technique I have to learn and make work.
Essentially, what I think is that historically/ archaeologically, we don’t know the past well enough until we can re-create as much of it as possible at will as closely to the material culture and artefacts of the period. Some might argue that we’ll never get perfect accuracy, but I think that is a pointless claim, although it might be technically correct when you get down to the precise chemistry (E.g. there are few modern sheep with wool anything like medieval ones, so reproduction cloth won’t be quite right), it ignores that we can know and be sure of a great deal without any problems, and part of that is knowing that there will be differences in behaviour between medieval and modern cloth.
Hopefully you will follow me as I get better acquainted with how our ancestors did things, and the skills they learnt and used, as well as the exciting stuff like molten metal and fire.