The history of silver refining in New Spain, 16c to 18c: back to the basics

The refining of silver ores in New Spain was defined by the chemical nature of the silver ore. Argentiferous galena (lead sulphide) could only be refined by smelting (36% silver produced), irrespective of silver content, and amalgamation (64%) could only be applied to the silver sulphide ores. Both processes were transferred from Europe, but amalgamation was transformed by local expertise from a recipe of limited application to an industrial-scale solution for refining sulphidic silver ores. Its implementation shaped the environmental history of colonial silver refining in the New World. Mercury was consumed mainly through its chemical conversion into calomel, with minimal emissions of volatile mercury. Waste silt and liquid mercury in the soil and waterways were its main legacy. Smelting created a greater impact on the environment of New Spain, via lead in lead fumes as the main heavy metal issued to the air, and its depletion of woodlands. This article argues that a technical analysis of period refining practices in New Spain reorients our understanding of Spain’s imperial relations with its New World colonies, of the role of local knowledge in a global economy of silver production, and of environmental issues in colonial history. It thus speaks to the problem of unpacking the complex web of relations that composed early European imperialism, in which were enmeshed commodities such as silver, cotton and sugar.     

Was He Murdered Or Was He Not?—Part I: Analyses of Mercury in the Remains of Tycho Brahe

World‐renowned Renaissance astronomer Tycho Brahe died on 24 October 1601, after 11 days of illness. Several conspiracy theories regarding his death have been aired, the first shortly after his death by William Shakespeare in the play Hamlet, published in 1603. A key factor in the still lively debate is whether he was administered mercury—as medicine by his own hand, or as poison by an unfriendly hand. In 2010, Brahe's grave was reopened and samples of his bones, hair, teeth and the textiles were procured and analysed. Here, we present evidence that Brahe was not administered lethal doses of mercury.     

Sub‐micron spongiform porosity is the major ultra‐structural alteration occurring in archaeological bone

Total pore volume and pore size distribution are indicators of the degree of post‐mortem modification of bone. Direct measurements of pore size distribution in archaeological bones using mercury intrusion porosimetry (HgIP) and back scattered scanning electron microscopy (BSE‐SEM) reveal a common pattern in the changes seen in degraded bone as compared to modern samples. The estimates of pore size distribution from HgIP and direct measurement from the BSE‐SEM images show remarkable correspondence. The coupling of these two independent approaches has allowed the diagenetic porosity changes in human archaeological bone in the >0.01 µm range to be directly imaged, and their relationship to pre‐existing physiological pores to be explored. The increase in porosity in the archaeological bones is restricted to two discrete pore ranges. The smaller of these two ranges (0.007–0.1 µm) lies in the range of the collagen fibril (0.1 µm diameter) and is presumably formed by the loss of collagen, whereas the larger pore size distribution is evidence of direct microbial alteration of the bone. HgIP has great potential for the characterization of microbial and chemical alteration of bone. Copyright © 2002 John Wiley & Sons, Ltd.     

Getting Started: Objectives and Justifications in the History of Neurology

Contemporary historiographical ideas have the potential to enrich the history written by practicing neurologists. Neurology is a science, and historians of neurology might profit from considering the experiences of historians of other sciences. An explicit consideration of the range of possible objectives, justifications, sources and methods of historical research may open new and exciting avenues of inquiry. Any plausible answer to the question, “What does a historian do when he or she sits down to write history” helps an historian to develop the structure of his or her project. The selection of sources for a historical study is improved, if also expanded, by understanding its aims.     

两件西汉时期鎏金与鎏银青铜器镀层中的金属化合物

采用金相显微分析、环境扫描电子显微镜、X-射线衍射、X-射线荧光对两件西汉时期的鎏金与鎏银青铜马镳进行了分析,揭示了西汉时期鎏金与鎏银青铜器的部分金相学特征和部分金属化合物,研究结果表明我国西汉时期已采用了金汞齐与银汞齐在铅锡铜合金表面火法鎏金和鎏银技术。     

Hair today,gone tomorrow: Analysing potential mercury exposure in 19th-century New Zealand gold miners using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry

Toxic metal or element exposure has the potential to cause significant negative health effects in human populations. During the goldrushes of the colonial period, mercury amalgamation was one of the most common methods of extracting gold from alluvial deposits or crushed ore, and exposure to mercury was an occupational health hazard. In this study we examine mercury exposure in mining populations from New Zealand’s first major goldrush, which began in Central Otago in 1861. We explore mercury toxicity through laser ablation inductively coupled mass spectrometric analysis of archaeological hair and sediment samples associated with the Tuapeka goldfields. Our analysis highlights ubiquitous low-level mercury exposure on the goldfields, as well as one individual with such high mercury concentrations in their hair that we suspect direct mercury intake, perhaps medicinally, rather than from environmental contamination.     

The connectivity of pore space in mudstones: insights from high‐pressure Wood's metal injection,BIB‐SEM imaging,and mercury intrusion porosimetry

Study of the pore space in mudstones by mercury intrusion porosimetry is a common but indirect technique and it is not clear which part of the pore space is actually filled with mercury. We studied samples from the Opalinus Clay, Boom Clay, Haynesville Shale, and Bossier Shale Formations using Wood's metal injection at 316 MPa, followed by novel ion beam polishing and high‐resolution scanning electron microscopy. This method allowed us to analyze at high resolution which parts of a rock are intruded by the liquid alloy at mm to cm scale. Results from the Opalinus Clay and Haynesville Shale show Wood's Metal in cracks, but the majority of the pore space is not filled although mercury intrusion data suggests that this is the case. In the silt‐rich Boom Clay sample, the majority of the pore space was filled Wood's metal, with unfilled islands of smaller pores. Bossier Shale shows heterogeneous impregnation with local filling of pores as small as 10 nm. We infer that mercury intrusion data from these samples is partly due to crack filling and compression of the sample. This compaction is caused by effective stress developed by mercury pressure and capillary resistance; it can close small pore throats, prevent injection of the liquid metal, and indicate an apparent porosity. Our results suggest that many published MIP data on mudstones could contain serious artifacts and reliable metal intrusion porosimetry requires a demonstration that the metal has entered the pores, for example by Wood's metal injection, broad ion beam polishing, and scanning electron microscopy.     

Influence of porosity on lipid preservation in the wall of archaeological pottery

Porosity of archaeological pottery is a key parameter used to assess its ability to trap lipids during the use of the pot and to preserve them over time. Mercury intrusion porosimetry and gas chromatography were used to study the distribution of porosity and the preservation of lipids in different chrono‐cultural contexts. The data obtained show that the porosity pattern, related to the raw materials and the savoir‐faire of the potters, influences the amount of lipids accumulated in the pottery. A significant overall porosity together with a high level of small pores is generally favourable for the preservation of lipids, but variations related to the environmental context are observed.