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Yale University industrial ecologist Thomas E. Graedel likes to point out in his lectures that when you hold a cellphone, you’re holding half the periodic table of elements in your hand. The number of minerals used in electronics has ballooned over the years, and now the industry finds itself highly dependent on some substances whose supply is more precarious than we’d like. Graedel was part of a U.S. government committee that looked at the ”criticality”—the combination of importance and supply risk—of a number of key minerals. Some of the most critical are found in cellphones. The ones to worry about, says Graedel, are difficult to find substitutes for and are produced only as by-products of something else, so their own supplies are constrained. Gallium and indium fall into that category. Graedel has also been examining the fact that a more affluent global population may cause even common minerals like copper to become scarce.


Use: Wires, cables, and general infrastructure

Top suppliers: Chile, United States, Indonesia, Peru

Projected scarcity: Copper is extensively mined and has a huge reserve base, but recent analysis has found that for the world population to attain North American affluence by 2100, more copper would be required than exists in the Earth’s crust.


Use: LEDs, lasers, solar cells, and RF circuits

Top suppliers: China, Germany, Kazakhstan, Japan, Russia

Projected scarcity: Gallium is a by-product of the production of other, more important metals, and so its supply is entirely dependent on the demand for those other metals.


Use: Insulator in cutting-edge chips

Top suppliers: Australia, South Africa

Projected scarcity: Even though it is found in the abundant mineral zircon, hafnium is rarely refined, and there is little production data available. Because its use is so new, it’s hard to say when it might become scarce.


Use: Transparent electrodes that control the pixels in LCD displays

Top suppliers: China, Canada, Japan

Projected scarcity: The price of indium has shot up recently. Unless new resources are found and recycling improves, indium could be scarce by 2020.


Use: High-performance capacitors in cellphones and cars

Top suppliers: Australia, Brazil

Projected scarcity: Tantalum will probably not be scarce until after 2030 . But a U.S. government report notes that suppliers can easily hold capacitor makers hostage to price increases.


Use: Main component of lead-free solder

Top suppliers: China, Indonesia, Peru

Projected scarcity: It’s mined extensively and has a huge reserve base, so even if lead solder is eliminated worldwide and the world population’s affluence grows, tin will not become scarce.

Sources & Notes: Price, production, and reserve base data are from the U.S. Geological Service’s Mineral Commodity Summaries 2007 and 2006 Mineral Yearbook . The criticality index is from the U.S. National Research Council’s report Minerals, Critical Minerals, and the U.S. Economy (November 2007). Analysis of copper and tin are from ”Metal Stocks and Sustainability,” by R.B. Gordon et al., Proceedings of the National Academy of Sciences , 31 January 2006, pp. 1209�1214. Projected scarcity of tantalum and indium were determined by dividing the reserve base by 2006 production.

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Why the Internet Needs the InterPlanetary File System

Peer-to-peer file sharing would make the Internet far more efficient

12 min read
An illustration of a series
Carl De Torres

When the COVID-19 pandemic erupted in early 2020, the world made an unprecedented shift to remote work. As a precaution, some Internet providers scaled back service levels temporarily, although that probably wasn’t necessary for countries in Asia, Europe, and North America, which were generally able to cope with the surge in demand caused by people teleworking (and binge-watching Netflix). That’s because most of their networks were overprovisioned, with more capacity than they usually need. But in countries without the same level of investment in network infrastructure, the picture was less rosy: Internet service providers (ISPs) in South Africa and Venezuela, for instance, reported significant strain.

But is overprovisioning the only way to ensure resilience? We don’t think so. To understand the alternative approach we’re championing, though, you first need to recall how the Internet works.

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