The U.S. dollar [url=http://parajumpersjackets1.tumblr.com/]parajumpers jackets[/url] is the world reserve currency of choice. It the currency that most of the planet business [url=http://hollister-pas-cher-france.tumblr.com/]hollister pas cher france[/url] is conducted in, and it what most nations hold in their central banks, in addition to national currencies, in case of catastrophe. The idea is that since the U.S. government is always good for it money, and always pays its bills, the dollar and U.S. treasury bills are the safest bets around. But what if they aren? What happens if [url=http://parajumperstilsalgs.tumblr.com/]parajumpers til salgs[/url] thanks to our repeated debt ceiling debacles [url=http://hollister-clothingfrance.tumblr.com/]hollister clothing france[/url] and threats to go into default, people stop trusting in the dollar? That the question that Joe Nocera, Charlie Herman and I discussed on this week episode of WNYC Money Talking; you can listen below.

If you look at foreign purchases of treasury bills before and during debt ceiling fights over the last three years, it a legitimate question to be asking. A recent Goldman Sachs research report shows that during the last standoff in August of 2011, purchases went down significantly and rebounded only after Congress had come to an agreement to raise the ceiling and honor US debt. At some point, if we keep making markets nervous, it reasonable to think that central banks around the world will get fed up and start moving to a different balance of reserve currencieserhaps putting more in euros, especially given that Europe is now in better shape than it was two years ago, or, eventually, into emerging market currencies like the RMB.

To be fair, wee a long way from the dollar position being usurped. But it worth remembering that even before this crisis, economists around the world have been advocating for a new reserve system based on , rather than just the dollar, for financial security reasons.

After all, the fact that [url=http://parajumper-jackets.tumblr.com]parajumper jackets[/url] we have such a privileged borrowing position is one of the reasons that we can rack up so much debt, run a huge current account deficit and make the global financial system as unbalanced as it is. If the dollar lost some of its street cred, it would make borrowing a lot more expensive for the US and throw the markets into short and possibly even medium term chaosut it might ultimately lead to a more balanced monetary system.

For many years finding large deposits of the world\'s most important commodity after oil has been difficult and largely haphazard.

Small iron deposits are common but the giant deposits that the big miners are looking for are much harder to find.

The problem is that geologists still don\'t know how those huge ore bodies form and that makes it hard to look for them.

But three new studies may help solve those mysteries.

The University of Alberta\'s Professor Jeremy Richards and Dr Jamie Wilkinson of the UK\'s Imperial College have been examining iron ore deposits above subduction zones, where continental plates slide under each other.

Prof Richards argues that large iron ore deposits form when warm magma [url=http://letscanadagoosevest-no.tumblr.com/]canada goose vest[/url] pockets are shaped by distinct plate movements, surrounded by reactive rocks and are regularly flushed with fresh magma and groundwater.

However Dr Wilkinson thinks large ore deposits form when underground [url=http://parajumpersusa.tumblr.com/]parajumpers usa[/url] magma is saturated with sulphide, which concentrates the tiny trace amounts of metal in the magma.

Heat then binds the tiny molecules [url=http://parajumperssalg.tumblr.com/]parajumpers salg[/url] of the same metal together until masses of gold, iron and nickel and other metals are formed.

He says those masses cool and large metal deposits are left.

Macquarie University\'s Professor William Griffin, who\'s been studying the distribution of diamond, gold and metal deposits, believes that the earth\'s mantle holds the key.

He thinks the mantle acts like a mould that guides upwelling magma into pockets.

If those pockets [url=http://billigcanadagoosejakke.tumblr.com/]billig canada goose jakke[/url] and the passages that lead to them from the earth\'s core [url=http://parajumperskodiakwomen.tumblr.com/]parajumpers kodiak women[/url] are a certain shape and size, and made out of certain materials, then large ore deposits are likely to form when the magma cools.

The three reviews are the first to give a geochemical footprint for miners and geologists to look for when searching for large ore deposits.

They are part of a collection of articles on economic geology, and argue that the search for giant deposits could potentially be made more efficient.

The studies will be published in the UK journal Nature Geoscience on Monday.