archaeometallurgy

This aquamanile in the form of a knight on horseback was cast in 2015 in Bastian Asmus’ workshop, and leans heavily on an original from the 13th century. It was cast in bronze by the lost wax technique.

Next to lion and griffin aquamanile a knight on horseback was a widely used form of aquamaniles . One of these  I made earlier this year and cast it in bronze in my workshop.  The original aquamanile is from the 13th century from northern Germany, probably around Hildesheim.

This object displays the impressive skills of the 13th century artists and foundrymen. The arms, legs and stir-ups are modelled full round, which adds quite a bit of complexity to the preparation of the casting mould; especially when we are considering that these moulds were not made like modern investment moulds, but by applying moulding loam to every bit of wax surface.  The materials thickness of the bridle or stir-ups is in places less than 2mm in diameter. The knight is not modelled separately but cast in one piece with the horse.

Just as the griffin aquamanile this reconstruction can be seen in the newly opened European Hanseatic League Museum in Lübeck, Germany.

 Literature

Details of a second cast of a self-portrait of Peter Vischer (1455-1529) from the shrine of Saint Sebald, Nuremberg. Original size of head: 6 cm.

I know the title says Peter Vischer the Elder, however this is a post on one piece of his work only: namely the self portrait of Peter Vischer. When I returned from a fantastic conference on Medieval Copper, Bronze and Brass in Dinant and Namur, Belgium,  I remembered that back in the nineties I had to make journeyman’s piece towards the end of my apprenticeship as an artistic bronze founder. This journeyman’s piece is the self portrait of Peter Vischer the Elder, the other two where portrait medals of Martin Luther and Albrecht Dürer, cast in a specialised medal casting technique. The self-portrait of Vischer is located at the front end of the shrine of Saint Sebald. The shrine was commissioned in 1499 and was finished in 1519. Peter Vischer the Elder was granted the title of  a master in the Rothschmied Handwerk in 1489. The Rotschmied or Rotgießer could be literally translated as red smith or red caster. Although the name would suggest the Rotgießer were obliged to work with red metals, such as copper and  copper-tin alloys only, or the Gelbgießer was obliged to work only with yellow metal, i.e. brass, this was not so: Many Rotgießer were working with brass and/or red brass as well. There was a distinction between the Rot- and the Gelbgießer, though and that had to do with the preferred moulding material: Rotgießer were working with moulding loam and Gelbgießer with moulding sand . Red casters were also casting larger objects than the Gelbgießer. It is most likely that there was no clear cut boundary between the two casting trades.

The self-portrait of Peter Vischer the Elder

Coming back to the self-portrait of Peter Vischer the Elder: Here I show a few aspects of the raw cast and explain why this piece secured me the first prize in the competition of the chamber of handicrafts in Germany: The cast is near flawless. It was cast in one piece in the lost wax technique. There are only four core supports, two of which are the nails seen in the images. The other two were placed in the top of the head and near the bottom of the hem at the backside. The gating system is attached in a manner as to leave the original surface fully intact. I left this piece in this state, because it shows the surface quality that can be achieved. The brownish colour stems from the various oxides of copper and tin, that develop upon contact with the moulding material and form a thin skin, which can be easily removed by ways of filing, scraping, or pickling.

References

This is part three of the series on slag microscopy. Today is about sample mounting: we use a cold mounting procedure, i.e. samples are mounted in resin. I have talked about  the find documentation process  and the cutting of the sample in parts one and two.

Sample mounting: Three different sizes of sample cups: 20, 32 and 40 mm.

The following things are needed for this:

• cold mounting resin and curing agent
• mixing cup
• sample cups
• ultrasonic bath
• IMS
• optional: exsiccator and vacuum pump
• safety goggles
• lab coat or an apron Continue reading