According to the video 9 Shocking Facts from the Quran!

Iron is not natural to the Earth. It did not form on the Earth but came down to Earth from outer space. This may sound strange but it is true. Scientists have found that billions of years ago the Earth was stuck (sic) by meteorites. These meteorites were carrying iron from distant stars which has exploded.

The presenter then relates this fact with a verse from the Quran.

We sent down Iron with it's great inherent strength and its many benefits for humankind.

Did iron form on Earth? Did it come from outer space? Was all iron on Earth added after the Earth formed?

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    One of the claims is that all iron on Earth comes from meteorites (as opposed to be present when the Earth was formed. That is addressed/clarified on Geology.SE. It then goes on to suggest that the Quran said iron was "sent down". The obvious interpretation is that they authors meant sent down from Heaven, not sent down from outer space, but that isn't something we can resolve with evidence. – Oddthinking May 9 '18 at 2:35
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    If you take a broad enough view, all matter on Earth cam from outer space. In fact, an even broader view could claim that all matter on Earth is still in outer space. – Kamil Drakari May 9 '18 at 16:27
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    I don't think the Quran verse helps. It is a separate claim. – Oddthinking May 10 '18 at 1:08
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    There is some basis to this claim. Almost all of the iron and steel artifacts dating roughly before 1200 BC were meteoric iron. While peoples of that time and before didn't know how to smelt iron ore, they did know how to make a fire hot enough to be able to work steel that had fallen from the sky. The iron age, where peoples finally had learned how to smelt (primordial) iron ore, came later. The iron we use now is almost entirely primordial. If you want to call that too as having fallen from the skies, well it did, but it did so before the planet existed as a planet. – David Hammen May 14 '18 at 3:13
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    The claim "Iron is not natural to the Earth." is wrong. Iron is a primordial element that was present in the material from which our planet was formed. In that respect it is no different from many other chemical elements. It is true that some more iron has arrived to Earth from falling meteorites during the entire "lifetime" of the Earth. It is also true that natural spontaneous fission of uranium (and possibly other nuclides) will have produced a bit of iron. But the contribution from such "later" sources is negligible in comparison of the enormous amounts of primordial iron. – Jeppe Stig Nielsen Sep 21 '18 at 11:37

Nuclear fusion is the mechanism by which most atom nucleii have been formed from the original plasma present after the Big Bang. It requires incredibly hot temperatures not found in outer space. Since the Big Bang, nucleii have been formed in stars and then ejected in outer space at the end of the life of those stars.

See for instance: Nasa's Cosmicopia

Since Earth was formed by the aggregation of material in our solar system (like the other planets), there has not been enough energy to produce fusion (i.e. the temperature was much too low. Most of the iron present on our planet (and the core of the planet is mainly composed of iron & nickel) has thus been produced in stars that have disappeared before the Solar system was formed.

More details on phys.org

There might be iron produced on Earth by the radioactive decay of e.g. uranium, but this should be a very small quantity compared to the amount present when Earth was formed.

See this page from the Berkeley Lab

So, the formal answer to your question, is NO, not all the iron present on Earth came from outer space, but most of it did.

Some of the information contained in this post requires additional references. Please edit to add citations to reliable sources that support the assertions made here. Unsourced material may be disputed or deleted.

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    But then again, virtually all the elements that comprise the earth's crust (and atmosphere) "came from outer space". – Daniel R Hicks Sep 11 '18 at 11:52
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    Welcome to skeptics. We don't allow unreferenced answers on this site. Please correct yours. – Sklivvz Sep 11 '18 at 21:17
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    That should be a big NO to the question as the majority of iron on earth arrives as part of the formation of the planet and not later from meteoric impacts after the original planet settled down. But then, the claim itself is confused about this when stating "iron is not natural to the earth" which is clearly wrong in any meaningful sense. – matt_black Sep 21 '18 at 15:14

The mass of the Earth is approximately 5.98×10²⁴ kg. In bulk, by mass, it is composed mostly of iron (32.1%), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%), calcium (1.5%), and aluminium (1.4%); with the remaining 1.2% consisting of trace amounts of other elements.

Source: Abundance of the chemical elements

The proto-Earth grew by accretion until its interior was hot enough to melt the heavy, siderophile metals. Having higher densities than the silicates, these metals sank. This so-called iron catastrophe resulted in the separation of a primitive mantle and a (metallic) core only 10 million years after the Earth began to form, producing the layered structure of Earth and setting up the formation of Earth's magnetic field.

Source: History of Earth

So: no, not all iron on Earth came from outer space. Iron was part of the planet already from the beginning.

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    Is this a yes or no answer? – Oddthinking Sep 12 '18 at 7:55
  • Given that all the material in the proto-earth came from outer space, it didn't after all spontaneously come into being at some point, the iron on the proto-earth also came from outer space :) – jwenting May 27 at 6:07

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