archaeometallurgy

Just out now: A paper that summarises several years worth of medieval bell casting projects  (Asmus 2023). It is part with my ongoing research focus on the development of metal casting in the medieval period, roughly encompassing the period between AD 800 and 1600.

The paper is open access and can be accessed here.

Abstract

This paper presents key results from experimental work on traditional bronze casting, focusing on early to high medieval bells, roughly between the 8th and 12th century AD . It demonstrates that combining craft, historical sources, and modern science can effectively revive lost technologies. The reconstruction is based on Theophilus Presbyter’s Schedula Diversarum Artium, dated to the early 12th century, whose precise instructions were critical, though several field-scale experiments were required to refine the process.

These experiments are part of broader research into medieval large-scale casting methods in central Europe. The paper argues that more than experimental archaeology or traditional craft is needed to understand and recreate lost technologies. Researchers must invest significant time mastering materials, tools, and techniques to grasp craft processes fully. Brief experimental engagements fail to capture the depth of these traditions. This approach bridges archaeology and hands-on practice, challenging conventions in both traditional craft and mainstream academia.

Literature

 Todays article mostly is on the reverberatory furnace.  However, this is the beginning of a small series of articles that are concerned with casting of larger objects: Cannon, bells and statuary art. Only recently my colleagues and I published an article on the written evidence with regards to the casting of the large bronze statues. Or so we thought; the statues from the Hofkirche in Innsbruck were made from brass  (Mödlinger, Asmus & Ghiara, 2024).

A reverberatory furnace hypothesis based on a 16th description (Asmus, in prep)

The beginning of the 16th century is commonly accepted as the end of the middle ages and the beginning of the modern age. This does also apply to the metallurgical trades, because around the same time the reverberatory furnace makes its appearance in Europe. Seemingly out of nowhere, or at least without any apparent predecessors, the reverberatory furnace manifests itself as fully evolved piece of technology in the metal trades. Leonardo da Vinci and Buonaccorso Ghiberti, nephew of the famous Lorenzo Ghiberti left us with sketches of these furnaces. Artists and scholars like Vannoccio Biringuccio (1540) or Benvenuto Cellini (1974, 2005) left us with treatises, where they provide insights into the design and use of these furnaces.

This type of furnace appears more or less suddenly at the beginning of the modern era. There are nor real preceding furnace designs from the middle ages in Europe, so there is a possibility that this concept arrived in Europe as a new concept. The reverberatory furnaces are one key component in the Industrial Revolution (Bulstrode 2023) as puddling furnaces for the making of steel, from scrap iron and also from raw cast iron.

A reverberatory furnace for Vianden

The reverberatory furnace for Vianden is a new reconstruction based on a 16th century treatise of the founding of cannon (Asmus, in prep). The experiment follows the instruction closely and  will  use it to cast a cannon, based on one cannon found at castle Brandenbourg, Luxemburg. It is one of the two cannon made by Casper Bux from Vianden in the 16th century.

The signature of Casper Bux von Vianden.

The cannon mould will also be made experimentally following a variety of 16th century at the Castle Vianden. The whole process can be seen live at the castle.

A reverberatory furnace not only for cannon

The Vianden  reverberatory furnace is far more than only for cannon casting. With the very same furnace we can cast bells by or the cast of statuary art. As a fully trained bronze caster I do have strong interest also in bronze sculpture, and from the above mentioned Cellini treatise we know that his Perseus with Medusa was made by such with the reverberatory furnace.

To this end I hope that we can use the  Vianden reverberatory many times for the purposes of contributing towards the understanding the intricacies of Renaissance bronze casting and beyond.

References

A new paper on Renaissance Casting Technology was just published. It looks both, into the chemical composition of the utilised alloys, as well as into the primary sources concerning the manufacture of the cenotaph of Emperor Maximilian I.

Get the full paper here https://doi.org/10.1007/s40962-024-01299-4

The 28 “Schwarze Mander” (Black Men) are undoubtedly amongst the most magnificent monumental brass statues of the Renaissance. Commissioned by the Holy Roman Emperor Maximilian I for his funeral monument at the beginning of the 16th century, they were completed more than 30 years after the Emperor’s death and are now part of his cenotaph in the Hofkirche in Innsbruck. Revising the original manuscripts and letters exchanged between Maximilian I and the various artists sheds light on the manufacturing process and the challenges the artists encountered whilst producing the statues. Moreover, the alloys used in the manufacture of the statues, now all blackened due to patination processes, were identified through non-invasive chemical analysis of all the statues.

Introduction

The 28 Schwarze Mander are without a doubt amongst the most stunning brass statues of the Renaissance period. They were commissioned by Maximilian I, the Holy Roman Emperor, for his funeral monument in the early 16th century but took over 30 years to complete after his death. Originally, the emperor wanted 40 statues of ancestors and saints of the Habsburg family and 100 statuettes of other saints associated with the House of Habsburg, as well as a sarcophagus for the emperor himself. In the end, 28 statues (Table 1), 23 statuettes and 34 busts of emperors (of which only 21 have survived) were created. The sarcophagus was replaced by a cenotaph with the kneeling statue of Maximilian I, the four virtues and 24 marble reliefs. Maximilian I, at the end, was buried in Wiener Neustadt.

Get the full article here and finish reading it: https://doi.org/10.1007/s40962-024-01299-4

References