Gold from the Golden Coach originating in Suriname; Unknown provenance investigated by Amsterdam Museum, Vrije Universiteit Amsterdam and NICAS

The Amsterdam Museum has teamed up with VU University Amsterdam, Netherlands Institute for Conservation+Art+Science+ (NICAS) and Naturalis Biodiversity Centre to research the origins of the gold of the Golden Coach. For a long time, it was unknown where the gold leaf used to gild the carriage came from. An extensive study compared the composition of the gold with samples from Suriname and South Africa. A mystery has been solved: the gold turns out to have come from Suriname.

From 18 June 2021 to 27 February 2022, the Golden Coach was on display at the Amsterdam Museum after a restoration of more than five years. An exhibition highlighted diverse stories. Hundreds of cultural-historical objects gave a multifaceted picture of the history and use of the Golden Coach and the discussions surrounding the iconic means of transport. The exhibition paid extensive attention to the construction of the Golden Coach.
The carriage is made of Javanese teak. This wood is partly painted and partly gilded with gold leaf. This gold leaf gave the carriage its name. But where the gold came from was unknown until now. The exhibition raised the issue that, despite the prominence of the gold on the carriage, its origin had never been investigated. No documents from the late 19th century proved where the gold came from and possible archives have been lost. The provenance could only be investigated using today's techniques.

Annemarie de Wildt, curator at the Amsterdam Museum, did extensive research on the Golden Coach for the exhibition. She found it unfortunate that its provenance was unknown and also untraced during the five-year restoration. "The makers and initiators of the Golden Coach boasted that the gift to the new monarch Wilhelmina should represent the entire then Kingdom of the Netherlands. Thus, the carriage incorporated flax from Zeeland, leather from Brabant, wood from Java and ivory from Sumatra. However, Suriname, part of the Kingdom of the Netherlands at the time, did not seem to be represented. This raised questions for me and many others.

South Africa was a major exporter of gold around 1900 and the country had strong ties with the Netherlands, but in Suriname, people have been told for generations that the gold came from there. Enough reason to investigate the origin of the gold." De Wildt contacted the National Agency for Cultural Heritage and the Free University of Amsterdam and initiated research.

Gareth Davies is professor of Petrology - a field of research in geology that focuses on studying the composition of rocks and the conditions under which they formed - at VU University Amsterdam. Davies and his team started in the spring by comparing a piece of gold leaf from the Golden Coach, provided by the Royal Stable Department, with samples of gold from different regions in South Africa and Suriname, obtained from Naturalis.

Davies: "To compare gold, we look at the lead isotopes formed by the radioactive decay of the elements uranium and thorium. These differ by region. A clean sample is needed for that comparison. But the gold from the Golden Coach contained lots of lead particles that came from air pollution the coach was exposed to over the years, such as petrol. There was also lead-containing paint and glue. All those billions of particles of lead had to be removed. It was like having to remove one grain of sand from a pool full of grains of sand. A huge job that took over four months. In addition, our work was further complicated by the fact that we only had a small sample at our disposal. Gold leaf is 1 micron thick. That is 100 times thinner than a human hair."

Davies' team still managed to compare the lead concentration of the gold from the carriage with samples from the different regions. This showed that the gold from the Golden Coach was very different from the samples from South Africa. "We can say with certainty after careful analysis that the gold from the Golden Coach did not come from South Africa. From a historical perspective, South Africa or Suriname are considered possible options. The results from our research are fully consistent with Suriname as the country of origin of the gold on the Golden Coach," Davies said.

After gold was found in Suriname in 1876, large-scale gold mining took off in the following decades. A railway line was even built to reach the reserves south of Paramaribo. The gold from the carriage most likely came from that area. Davies: "For now, we can show that the gold from the Golden Coach is most similar in composition to the sample originating from a gold mine on the Suriname River, near Brownsberg, in the Brokopondo region." De Wildt thinks this is a logical conclusion because in the late 19th century, when the Golden Coach was made, a lot of gold was mined in this area. "It is great that there are now research methods that can confirm the urban myth that the gold from the carriage came from Suriname."

The VU Amsterdam team would like to investigate exactly which gold mine in Suriname the gold came from, but would need hundreds of samples from the region to do so. It will also take months of work to analyse all the samples. In addition, the team wants to characterise gold deposits from other parts of the world to help museums and collectors understand the provenance of other gold artefacts. Funding is needed for this.

The research into the gold of the Golden Coach is not the only research initiated by the Amsterdam Museum in this project. Prior to and during the exhibition, the museum also conducted research into sentiment about the Golden Coach and its future. With a specially developed mobile research installation, the museum travelled all twelve provinces to question Dutch people about their knowledge, memories and opinions about the Golden Coach. In addition, the Amsterdam Museum commissioned research firm Motivaction to conduct a quantitative survey and asked visitors in the exhibition about their views. These surveys showed that although the debate about the Golden Coach seems polarised at first glance, most Dutch people actually agree: they want the state-owned carriage to be preserved and on display. Only on the ideal way to achieve that, opinions differ.

"The role of museums is changing. As a museum, you cannot exhibit a controversial object alone. You have to facilitate and further the social debate. By providing space for new perspectives, starting conversations and doing research," says Margriet Schavemaker, artistic director of the Amsterdam Museum.

On Monday 12 September 2022 at 15.00, the Amsterdam Museum will present the results of all the research it conducted or commissioned with partners in a symposium. Both into the gold of the Golden Coach and into sentiment about the coach. The symposium will take place in the main hall of Pakhuis de Zwijger in Amsterdam and is open to everyone free of charge.