how is iron found in nature?

Question

is it found as the elements by itself, or in a compound?
please explain
thanks.

Answer 1

This is a good question, and much deeper than it first seems.
All the above answers are correct, but it is interesting to know how iron forms in the first place:

When a star forms, it is made up mostly of hydrogen with a little helium. As it condenses, the hydrogen goes through a fusion reaction, to produce helium and vast amounts of energy; which we see as sunlight. When all the hydrogen is used up, the helium fuses to form carbon, then the carbon will fuse to produce other elements, and so on through the periodic table.

When the fusion reaction produces iron however, it stops; because the iron nucleus is stable, and it takes more energy to cause iron to undergo a thermonuclear reaction than the reaction would produce. For the smaller stars, iron is the end product, and the star will then gradually lose its source of energy.

If however, the star is a very large star (much larger than our sun), its tremendous mass will cause it to continue to contract until the force is strong enough to overcome the nuclear stability of iron. The star will then explode in a tremendous burst of energy (a supernova), fusing iron and producing the higher elements of the periodic table.

The remnants of such an explosion may condense to form another star (a 'second generation' star, like our sun). There will still be a lot of hydrogen left over to form another star, but there are also small amounts of other elements which gradually coallesce under gravity to form planets, like our earth.

Iron therefore, is the end result of the thermonuclear reaction of a star, and it and the other elements found on earth are the products of an exploding star.

Answer 2

Where Is Iron Found

Answer 3

Iron is essentially ubiquitous. You can find pyrite (iron sulfide) or hematite (iron oxide) or iron hydroxide (generally called geothite or limonite) in just about any rock or sediment. Even when these iron minerals are absent, many other common minerals are present that contain iron as a primary constituent (biotite, various amphiboles, many different carbonates (like ankerite, siderite). Even sandstones that are essentially composed of quartz and nothing else usually contain some iron oxide or iron oxy-hydroxide as coatings on the individual grains. Because iron reacts readily with oxygen and water, native (metallic) iron is rarely found in the near surface environment.

Take something made of iron and leave it outside for a year, and you can pretty well guarantee the formation of oxides and hydroxides (rust).

Answer 4

Magnetite and hemetite are the most common ores. Since iron reacts easily with the oxygen in Earth's atmosphere, most native iron comes from meteorites (the word for an element in pure form, uncombined with other elements is "native"). The earliest iron refined and used by humans was probably in the form of red ocher (hydrated iron oxide) clays.

Answer 5

In nature, iron is never elemental. However, it is everywhere in nature. Its found in trace amounts in most living organisms (especially humans). It is also found in the earth, in varying concentrations. The earth's crust contains about 2.8% iron, mantle about 5.8% iron, and core at 80% iron. The majority of our processed iron comes from iron ore in the earth's crust, which is made up of mostly iron oxides (around 65% iron).

Answer 6

All the answers provided are correct.

But there is one source of iron in relatively pure elemental form, and that is in iron meteorites. Iron and nickel are therefore the most abundant metals in metallic meteorites.
Iron meteorites were the first sources of iron to ancient people before they learned to smelt iron from ore (mostly haematite and magnetite).

Answer 7

Usually in iron ore minerals such as hematite (an iron oxide)

Answer 8

iron comes from iron ore.....an element

Answer 9

http://en.wikipedia.org/wiki/Iron_ore
http://mysite.du.edu/~jcalvert/phys/iron.htm