Let’s think about how iron came to existence and think about where iron came from. According to astrophysicist, iron, like all other heavy elements, is created in the center of massive stars and is expelled into space once this start exploded as supernovae at the end of their lives. The material then mixes with the interstellar matter and may form new stars and planetary systems. The most abundant metal in earth is known to be iron because their outer core of the earth is filled with iron and liquid (Fe-Ni alloy). Therefore, iron makes up to 34 percent of the Earth's mass and is the fourth most abundant element in the crust. That's why iron makes up to five percent of the Earth's crust and the seventy percent of the Earth's cores. In earth, Iron exist in the several forms such as carbonates and oxides representatively in the form of hematite, magnetite, and ilmenite. And then some iron exist in the form of sulfides. According to the stats, 800 billion tons of iron ore resources are available. This contains more than 230 billion tons of iron. Representative minerals are as I talked to you previously hematite, magnetite, great height, and some are in the form of pyrite and some other mineral in the form of ilmenite. Then I'll think about how iron ore formed in the beginning. Over 1.8 billion years ago, Earth’s oceans contained the abundant dissolved iron in the form of every 2 plus but, almost no dissolved oxygen was available. The iron ore deposits began forming when the first organism capable of photosynthesis began releasing oxygen into the water. This oxygen immediately combined with the abundant dissolved iron to produce hematite or magnetite. This mineral is deposited on the sea floor in great abundance, forming what are now known as banded iron formation. Banded iron formation was in the form of hematite mostly. This kind of iron ore are enriched in Australia or Brazil which used to be sea floor when the iron ore formed.