The Little Cation that Could

Lithium, the first element in the alkali metals group of the periodic table, may seem a strange choice as a subject for which to devote a whole issue of Elements. Why should you care about lithium? What can lithium do for you? Well, lots, as it turns out. Not only is lithium a critical metal for modern society, it is also becoming an increasingly important tool for Earth scientists.

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Perspectives on the History of the Raman Effect and its Implementation

Chandrasekhara Venkata Raman (1888–1970) reported the light scattering phenomenon that has become known as the Raman effect in 1928 (Raman and Krishnan 1928). This followed theoretical predictions by Smekal (1923) that such a phenomenon should exist. Raman initially used sunlight, and then the light from a mercury lamp, to excite the spectrum presumably produced when a photon of light lost a small amount of its energy to a molecular vibration.

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New Perspectives in the Industrial Exploration for Native Hydrogen

Hydrogen gas (H2), when combusted, produces heat and water. There is no pollution, just water vapor. When hydrogen combines with oxygen, there is no generation of carbon dioxide, no production of cyclic hydrocarbons, no sulfur oxides (SOx), no nitrogen oxides (NOx), no ozone cogeneration. It seems that hydrogen, along with efficient energy production, solves many of our pollution problems, from urban air pollution to global warming. In the so-called Hydrogen Age of the future (Holland and Provenzano 2007), H2 will be mainly produced by the electrolysis of water using electricity that itself is derived from renewable energy sources or nuclear power plants. Steam methane reforming (a catalyzed reaction at high temperature where CH4 is combined with water to produce CO2 and H2) will only be acceptable as a source of H2 if it is associated with low-cost CO2 storage. But, in this future energy landscape, what is the role of naturally occurring hydrogen, sometimes referred to as native hydrogen?

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Kimberlite: A Unique Probe into the Deep Earth

With all due respect to basalt, and I appreciate a granite as much as the next person, kimberlite is hard to beat. But what is a kimberlite? Kimberlites may be classified as igneous rocks but it is difficult to know how exactly to describe them in terms of magma, at least in any conventional sense of the word. Kimberlites tap the deepest recesses of our planet that we can sample. Propelled by a formidable volatile load, kimberlite melts transit hundreds of kilometers of mantle and crust, perhaps in just a few days, to form unique ballistic deposits at Earth’s surface. Kimberlites accumulate and transport ripped-up bits from throughout most, if not all, of their ascent path, including diamond, that classic gem of desire with its remarkable qualities that have fueled a global market. Indeed, much of our understanding of kimberlite is owed to the intrepid explorers who searched for and studied elusive diamond deposits. Adding to the veil of petrological complexity kimberlites are often pervasively altered by fluids, some of which were magmatic but some of which were not. The study of kimberlites over many decades has revealed glimpses of their origins and the paths by which they have travelled.

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Deep-Ocean Mineral Resources

The mysteries and promise of the deep ocean rose to attention on the heels of military interest and technology after World War 2. Despite accounting for 70% of the Earth’s surface, almost nothing was known about the deep-ocean seafloor. That changed dramatically over the following 60–70 years, although our knowledge still remains patchy at best.

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A Personal Perspective on Layered Intrusions

Last year (2016), when I spoke at the Geological Society of America’s Penrose Conference on “Layered Mafic Intrusions and Associated Economic Deposits” held in Red Lodge, Montana, I noted that I gave my first professional talk some 35 years ago. As a young researcher back then, I had thought that all the interesting questions in layered intrusions were soon to be solved, leaving little room for me to make a name for myself. I was wrong!

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What is Sustainability in the context of Mineral Deposits?

Sustainable development is a term that all too often has been hijacked within our society by politicians and business promoters eager to endorse their “green” credentials. Yet human society requires sustainable growth in order to continue. However, in the context of much of society’s mineral resources what does sustainability actually mean?

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Cultural Heritage – Beautiful Questions

Nobel Prize–winner Frank Wilczek’s new book A Beautiful Question (2015) is a contemplation on the natural beauty of the universe and how scientists and philosophers, as far back as the ancient Greeks of Pythagoras and Plato, have asked questions about the underlying symmetry that exists in nature. Wilczek calls discovering underlying symmetries “finding Nature’s deep design,” and he develops the theme to include very modern questions of science.

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