The research, led by Valentina Pusateri of the Technical University of Denmark together with Mikołaj Owsianiak, Marja Rinne, Stig I. Olsen, Michael Z. Hauschild, and Sami Kara, tackles a stubborn blind spot in environmental accounting. Life cycle assessment, the standard tool for measuring the environmental footprint of products, has long struggled with how to treat metal resources. Recent methodological advances have shifted the focus from simple resource depletion toward resource dissipation: the idea that a metal becomes a genuine loss when it flows into a sink from which future users cannot realistically recover it. But existing methods typically treat all unrecovered metals as equally dissipated, ignoring the crucial fact that some stocks are far easier to tap than others, and that accessibility shifts as technologies mature and ore grades decline.

The Danish-Australian team proposed an elegantly simple criterion built on comparative profitability. A metal in a given anthropogenic stock is classified as dissipated when the net present value of extracting it from that stock is lower than the net present value of extracting the same metal from the reference stock, which the researchers defined as the upper continental crust, the most plentiful and dominant source of metals. In other words, if mining companies can always make more profit pulling copper out of the ground than out of a landfill, the landfilled copper is effectively inaccessible, no matter how concentrated it is. The authors were careful to stress that this does not mean the metal cannot physically be extracted; it means that in a global economy with a plentiful alternative source, the stock will not become the dominant supply, and its metal functions remain out of reach for the system as a whole.

To operationalize this dissipation quotient, the team assembled an unusually comprehensive economic dataset. They screened more than 500 publications and reports, ultimately extracting capital and operating expenditure data from 45 studies covering extraction of gold, copper, and iron from mine tailings, landfills, and hoarded stock such as end-of-life electronics. All costs were harmonized to 2024 euros using GDP deflators and exchange rates, and allocated per kilogram of extracted metal. Because revenues from metals are set on global exchange markets regardless of origin, the comparison reduces to a battle of costs: whichever source delivers metal more cheaply wins, and the loser is classified as dissipated.

The numbers reveal stark differences between the three metals. Extracting copper from anthropogenic stocks costs between roughly 6 and 670 euros per kilogram, while gold extraction runs between 28,000 and 44,000 euros per kilogram, a gap of about three orders of magnitude driven by the vastly different concentrations of the metals in waste streams. Iron sits at the bottom of the range, from about 0.07 to 120 euros per kilogram. Hoarded stock, meaning discarded phones, computers, and circuit boards, proved the most expensive source overall, despite its high metal concentrations, because collecting and dismantling small, complex devices is costly. Landfills showed the lowest average extraction costs for copper and iron, while tailings generally emerged as the most accessible stock type across the analysis.

The crucial twist comes from the reference side of the equation. Ore grades have fallen steadily since large-scale mining began, and the researchers projected this decline forward using an exponential decline model calibrated on historical data, cross-checked with a power regression approach. Copper ore grades have historically declined by about 1.72 percent per year, gold by about 1.05 percent, and iron by 0.61 percent. Because energy for mining and processing is the dominant cost driver and rises steeply as grades fall, the cost of primary extraction is expected to climb. At a 25-year horizon, the projected grade decline raises reference extraction costs by less than 10 percent. But by 300 years, the present value of costs is expected to increase by roughly 20 percent for gold, 200 percent for copper, and a striking 330 percent for iron relative to today.

Running the dissipation criterion across three time horizons of 25, 100, and 300 years produced a nuanced and somewhat counterintuitive picture. Accessibility generally increases with time, as primary mining becomes more expensive and the economic gap narrows. Gold consistently emerged as the most accessible metal, classified as non-dissipated in hoarded electronic waste, which aligns with the fact that gold recovery is already the main economic driver of e-waste recycling. Iron in tailings also performed relatively well. By contrast, hoarded iron, drawn from electronic waste where iron is merely a structural contaminant rather than a recovery target, was classified as dissipated across the entire range of uncertainty at every time horizon, with cost differences reaching minus 311 euros per kilogram at 300 years. Most other metal-stock combinations remained, on average, dissipated even at 300 years, though the uncertainty ranges were wide enough that many straddled the boundary.

The team then asked whether technological learning could flip these classifications. Using the classic Wright’s law framework, which links cost reduction to growth in cumulative output, they calculated the learning rates that emerging extraction technologies would need to break even with primary mining. For most combinations the required learning rates ranged from about 40 to 80 percent per doubling of output, far above the 15 to 25 percent considered realistic for emerging technologies, making a reclassification unlikely. Tailings were the notable exception. Copper recovery from tailings would need learning rates of only 25 to 40 percent, gold less than 20 percent, values well within reach as technologies mature. This finding dovetails with real-world developments, as copper is already being extracted from old mine tailings that were once written off as inaccessible.

The authors are candid about the limitations. Data availability was uneven, with no cost data at all for gold in landfills, and abandoned or dispersed technosphere stocks had to be excluded entirely. The assumption that anthropogenic metal concentrations stay constant over time may not hold if these stocks become active supply sources, and the assumption that metals recovered from waste fetch the same market price as virgin metal may fail where purity is lower. Yet sensitivity analysis suggested that the classifications are more sensitive to technology maturity and learning than to plausible shifts in reference ore grades. Recognizing this irreducible uncertainty, the researchers recommend a careful vocabulary shift: stocks meeting the criterion should be labeled potentially dissipative, and those clearing it potentially non-dissipative, rather than treated as certainties.

The implications reach well beyond academic methodology. Current footprinting approaches, including influential methods that assume everything not recycled within a given timeframe is dissipated, may systematically overestimate resource use impacts by ignoring the metal-, stock-, and time-specific nature of accessibility. The dissipation curves and breakthrough times generated by this framework could feed directly into next-generation life cycle impact assessment metrics, replacing crude recycling-rate proxies with economically grounded estimates of when, and whether, the metals we bury today will serve future generations. In a world where maximum technical circularity is estimated at only 30 to 40 percent and primary extraction will dominate for decades, knowing which of our discarded riches are truly lost, and which are merely waiting for the economics to turn, is a question whose answer is finally taking quantitative shape.

Subject of Research: Economic dissipation of copper, gold, and iron in anthropogenic stocks for resource footprinting

Article Title: Determining the dissipation of copper, gold, and iron resources in anthropogenic stocks based on extraction economics

Article References: Pusateri, V., Owsianiak, M., Rinne, M., Olsen, S. I., Hauschild, M. Z., & Kara, S. (2026). Determining the dissipation of copper, gold, and iron resources in anthropogenic stocks based on extraction economics. Journal of Industrial Ecology, 30(4), 1743-1759. https://doi.org/10.1007/s44498-026-00118-9

Image Credits: AI Generated

DOI: 10.1007/s44498-026-00118-9

Keywords: anthropogenic stocks, resource dissipation, life cycle assessment, circular economy, mine tailings, landfill mining, urban mining, ore grade decline, extraction economics, metal recycling, resource footprinting, technosphere

The Anthropocene concept was coined in recognition that human activities have ended the unusually benign environmental regime that characterized the Holocene, the epoch that encompassed the entire history of agriculture, cities and written civilization. But as the term migrated from stratigraphy into economics, politics, museum curation, education and the arts, it accumulated divergent and sometimes contradictory definitions. Some scholars stretch the Anthropocene back thousands or even tens of thousands of years to capture the cumulative footprint of early farming, mining and land clearance. The authors argue that while such extended interpretations portray the totality of anthropogenic change, they obscure the quantitatively established, dramatic rupture in Earth system behavior that began in the mid-twentieth century, and they cannot be defined in formal chronostratigraphic terms.

The technical case for the 1952 boundary rests on the stratigraphic record. Sediments deposited from the mid-twentieth century onward carry a distinctive and globally synchronous suite of signals: radionuclide fallout from atmospheric nuclear weapons testing, spheroidal carbonaceous fly-ash particles from fossil fuel combustion, a sharp rise in plastics and microplastics, and profound shifts in fossil assemblages driven by global species translocations and industrial agriculture. High-resolution analyses of archives such as the varved sediments of Crawford Lake in Canada have demonstrated that these markers appear together within a narrow time window, providing the kind of precise, correlatable geological evidence that formal epoch boundaries require. Human-driven environmental change of earlier millennia, by contrast, is diachronous and regionally variable, leaving no single globally synchronous horizon.

The authors emphasize that the distinction is not merely academic. A formally defined Anthropocene epoch enables quantitative and qualitative comparison between the stable Holocene and the increasingly unstable Anthropocene, a comparison already embedded in influential frameworks such as the planetary boundaries concept. That framework, which assesses how far humanity has pushed Earth system processes beyond safe operating limits, depends on a Holocene baseline against which modern departures can be measured. Six of nine planetary boundaries are currently judged to have been transgressed, and the annual Planetary Health Check tracks the deterioration. Without a stabilized Anthropocene definition, the authors warn, the conceptual foundation for such comparisons becomes blurred, weakening the scientific signal that policymakers most need to hear.

The Perspective also documents how deeply the Anthropocene idea has already penetrated institutions beyond geology. Dedicated research centers, policy programs and educational initiatives now bear its name. The United Nations Development Programme has framed new threats to human security in Anthropocene terms, the European Environment Agency has explored what it would mean to exit the Anthropocene, and the OECD’s PISA 2025 science framework incorporates agency in the Anthropocene as an educational goal. International law is grappling with the concept as well: the International Law Association’s committee on sea level rise has traced the implications of moving from Holocene assumptions of stable coastlines to an Anthropocene reality of rising seas, and the International Court of Justice issued a landmark advisory opinion on states’ obligations in respect of climate change in July 2025.

Underlying all of these applications is a single, consequential insight: the Earth system transformation of the Anthropocene is systemic, not piecemeal. Greenhouse gas accumulation, ocean warming and acidification, biodiversity loss, sediment cycle disruption, nutrient overloading and the spread of novel materials such as plastics and concrete are coupled processes, each amplifying the others. The authors argue that because the disruption is systemic, political responses must also be systemic rather than ad hoc. A unified Anthropocene epoch, they contend, would facilitate systematic, actionable climate and environmental policies by giving scientists, lawyers, economists and politicians a shared, precisely bounded reference point for what has changed and how quickly.

The geological evidence for that change is now overwhelming in its breadth. Humans have become the most significant global geomorphological driving force of the twenty-first century, moving more material than all natural erosion processes combined. The physical technosphere, the sum of human-made structures, machines and waste, has reached planetary scale, and its discarded products, from broiler chicken bones to concrete and plastics, are forming recognizable technofossils that will persist in the rock record. Earth’s sediment budget has been fundamentally reorganized, deltas and coastal wetlands are being transformed faster than they can adapt, and palaeontological signatures of the Anthropocene, including global species translocations and mass mortality assemblages, are demonstrably distinct from those of any previous epoch. Meanwhile, monitoring shows the acceleration continuing: record ocean temperatures in 2024, record-low Antarctic sea ice, warming-intensified drought, and documented declines in insect populations and wild mammal biomass.

The authors do not dismiss the value of broader, extended uses of the term. Environmental historians and archaeologists have shown that human reshaping of landscapes stretches back millennia, and understanding that deep history matters for questions of responsibility, equity and long-term change. But they insist that these interpretations represent a concept distinct from the Anthropocene epoch. Conflating the two, they argue, produces the worst of both worlds: the dramatic mid-twentieth-century rupture, which is the clearest and most politically urgent signal, gets diluted into a diffuse background of ancient impacts, while the genuine achievements of pre-industrial societies are recast as the origin of a crisis they did not cause. Clarity, they maintain, serves both scholarship and justice.

Looking forward, the Perspective maps out a research agenda in which a stabilized Anthropocene definition becomes a working tool across disciplines. In Earth science, it would sharpen the study of the anthropoclastic rock cycle, legacy contaminants re-released by melting glaciers, and the fate of microplastics as planetary markers. In law and governance, it would underpin efforts to adapt maritime boundaries, environmental obligations and international institutions to a planet no longer governed by Holocene assumptions. In education, it would anchor curricula that teach Earth system thinking and futures literacy. In the arts and humanities, it would provide a common chronological anchor for museums, exhibitions and imaginative work that seeks to make planetary change perceptible. The central purpose of a clear, formalized definition, the authors conclude, is to enable unified communication across the Earth sciences, social sciences, humanities, society and political and legal fora, so that the scale of the transformation can be grasped, debated and addressed with the seriousness it demands.

Subject of Research: Definition and interdisciplinary applications of the Anthropocene epoch

Article Title: Future directions for Anthropocene research and its applications

Article References: Zalasiewicz, J., Thomas, J. A., Cohen, K. M., Vidas, D., Sörlin, S., Waters, C. N., Head, M. J., Summerhayes, C. P., Leinfelder, R., Wallenhorst, N., Syvitski, J., McNeill, J. R., Robin, L., Williams, M., Cearreta, A., Ivar do Sul, J. A., Park, B. S., McCarthy, F. M. G., Han, Y., … Kuwae, M. (2026). Future directions for Anthropocene research and its applications. Nature Reviews Earth & Environment, 7(9), 633-646. https://doi.org/10.1038/s43017-026-00820-z

Image Credits: AI Generated

DOI: 10.1038/s43017-026-00820-z

Keywords: Anthropocene, Holocene, Great Acceleration, chronostratigraphy, planetary boundaries, Earth system science, Crawford Lake, technosphere, microplastics, geological epoch, environmental policy, international law