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Coltan, el nuevo oro.

Coltan: a new blood mineral

The controversy surrounding blood diamonds from the Democratic Republic of the Congo has made headlines over the past decade, but a relatively obscure mineral is also prompting international concern.

Human rights observers charge that coltan, used in electronic devices such as cellphones, DVD players, video game systems and computers, has been directly linked to financing civil wars in Africa, especially in the DRC.
Men, women and children are said to be forced at gunpoint to mine coltan that is then shipped out of the country at huge profits.
"Coltan is extracted under terrible working conditions in mines in eastern Congo," DanChurchAid, a Danish humanitarian nongovernmental organization, reported in 2006. "The United Nations reports child labour in Africa has significantly increased in coltan mines. In some regions of the Congo, about 30 per cent of schoolchildren are now forced to work in the mines."
On Friday, the Global e-Sustainability Initiative and the Electronic Industry Citizenship Coalition announced the launch of a Conflict-Free Smelter (CFS) program to combat the problem.
"The CFS program aims to identify smelters that can demonstrate through an independent third-party assessment that the raw materials they procured did not originate from sources that contribute to conflict in the Democratic Republic of Congo," stated the Electronic Industry Citizenship Coalition, a Washington-based industry group whose members include Apple, Celestica, IBM and Cisco.
Canadian New Democrat MP Paul Dewar introduced a bill in the House of Commons recently to fight the mining of conflict minerals in Central Africa, specifically in the Democratic Republic of Congo. If successful, Dewar's bill and similar initiatives around the world could prompt stricter guidelines and control on where the mineral is sourced by the major electronics producers.

What is Coltan?

Coltan, also known as columbite-tantalite, is a dull black metallic mineral containing the elements niobium and tantalum. Tantalum, a heat-resistant material that can hold a strong electrical charge, is used to make capacitors used in a wide variety of electronic devices, from cellphones to nuclear reactors. It is also used in high-heat-resistant steel alloys for applications such as aircraft engines.

Where is it found?

The mineral is found in a number of countries including Australia, Brazil, Canada and China, in addition to the Democratic Republic of the Congo.
Potential mines are also being explored in Saudi Arabia, Egypt, Greenland, Mozambique, the United States, Finland, Afghanistan, Venezuela and Colombia.


http://www.cbc.ca/news/technology/coltan-a-new-blood-mineral-1.894027

Crucigrama Coltan

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Coltan

COLTAN, MINERAL DE GUERRA

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Changing States of Matter

All matter can move from one state to another. It may require extreme temperatures or extreme pressures, but it can be done. Sometimes a substance doesn't want to change states. You have to use all of your tricks when that happens. To create a solid, you might have to decrease the temperature by a huge amount and then add pressure. Some of you know about liquid nitrogen (N₂). It is nitrogen from the atmosphere in a liquid form and it has to be super cold to stay a liquid. What if you wanted to turn it into a solid but couldn't make it cold enough? You could increase the pressure to push those molecules together. The opposite works too. If you have a liquid at room temperature and you wanted a gas you could use a combination of high temperatures and low pressures to solve your problem.

Phase changes happen when certain points are reached. Sometimes a liquid wants to become a solid. Scientists use something called a freezing point to measure the temperature at which a liquid turns into a solid. There are physical effects that can change the freezing point. Pressure is one of those effects. When the pressure surrounding a substance goes up, the freezing point and other special points also go up. That means it's easier to keep things solid at higher pressures. Just remember that there are some exceptions. Water (H₂O) is special on many levels. It has more space between its molecules when it is frozen. There's a whole expanding effect when the molecules organize into a solid state. Generally, when temperatures get colder, solids shrink in size. They become more dense.

CHEMISTRY TERM	PHASE CHANGE
Fusion (melting) Freezing Vaporization (boiling) Condensation Sublimation Deposition	Solid to Liquid Liquid to Solid Liquid to Gas Gas to Liquid Solid to Gas Gas to Solid

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