Barriers to and uncertainties in understanding and quantifying global critical mineral and element supply.

The critical minerals and elements are natural substances that are essential to modern life but have insecure supply. This lack of a secure supply clashes with the increasing importance of these elements, especially given their use in technologies needed to reduce global CO2 emissions and mitigate against anthropogenic climate change. In this contribution we review the by-product nature of the critical minerals and elements and the inherant uncertainties in reported critical mineral and element annual production as well as the relationships between these commodities and main-product metals and associated concentrates. We explore the geological and geographical barriers to critical mineral and element supplies, as well as how the lack of available data and the uncertainties in the data that are available hinder our ability to estimate global resources with confidence.

Mining in Papua New Guinea: A complex story of trends, impacts and governance.

Mining is often portrayed as a contributor to sustainable development, especially so in developing countries such as Papua New Guinea (PNG). Since 1970, several large mines have been developed in PNG (e.g. Panguna, Ok Tedi, Porgera, Lihir, Ramu) but always with controversial environmental standards and social impacts often overlooked or ignored. In PNG, mine wastes are approved to be discharged to rivers or oceans on a very large scale, leading to widespread environmental and social impacts - to the point of civil war in the case of Panguna. The intimate links between indigenous communities and their environment have invariably been under-estimated or ignored, leading many to question mining's role in PNG's development. Here, we review the geology of PNG, its mineral resources, mining history, key trends for grades and resources, environmental metrics (water, energy, carbon), mine waste management, and regulatory and governance issues. The study provides a unique and comprehensive insight into the sustainable development contribution of the mining industry in PNG - especially the controversial practices of riverine and marine mine waste disposal. The history of mining is a complex story of the links between the anthroposphere, biosphere, hydrosphere and geosphere. Ultimately, this study demonstrates that the scale of environmental and social impacts and risks are clearly related to the vast scale of mine wastes - a fact which remains been poorly recognised. For PNG, the promise of mining-led development remains elusive to many communities and they are invariably left with significant social and environmental legacies which will last for decades to centuries (e.g. mine waste impacts on water resources). Most recently, the PNG government has moved to ban riverine tailings disposal for future projects and encourage greater transparency and accountability by the mining sector, including its interactions with communities. There remains hope for better outcomes in the future.

Global platinum group element resources, reserves and mining - A critical assessment.

The platinum group elements (PGEs) are used in many technologies and products in modern society, especially auto-catalysts, chemical process catalysts and specialty alloys, yet supply is dominated by South Africa. This leads PGEs to be assessed as 'critical metals', signalling concern about the likelihood and consequences of social, environmental and economic impacts from disruptions to supply. In order to better understand the global PGE situation, this paper presents a comprehensive global assessment of PGE reserves and resources and the key mining trends which can affect supply. The data shows that global PGE resources have increased from 90,733t PGEs in 2010 to 105,682t PGEs in 2015, a 16.4% increase - despite global production of 2243t PGEs over this period. This suggests that the key issues facing the PGE sector are not geological or resource depletion, but clearly social, economic and environmental in nature - as highlighted by recent social issues in South Africa and volatile global economic conditions. Concerns over PGE supply reliability and the implications of any supply disruption will therefore continue to see the PGEs labelled as critical metals - but certainly not due to resource depletion.