Iron: Where it is found

What is it found in, and where on Earth?

Almost all iron ore is hematite or magnetite. Most of it comes from banded iron formations, sea-floor rocks laid down 3.7 to 1.8 billion years ago. Australia, Brazil and Russia hold about two thirds of the iron in known reserves.

Last updated 3 October 2026.

Minerals and ores

Iron is not usually found as the pure metal in rocks. It is bound to oxygen in ore minerals¹. The main ore minerals are hematite (Fe₂O₃, 70% iron) and magnetite (Fe₃O₄, 72% iron). Goethite, a hydrated iron oxide, has 63% iron. Limonite, a mixture of hydrated iron oxides, has up to 60%¹.

Hematite and magnetite are the minerals mostly used to make iron¹. Siderite, an iron carbonate (FeCO₃), is also an ore of iron²³. The name hematite comes from the Greek word for “blood-stone”¹.

Until recently, most enriched hematite deposits in the Pilbara of Western Australia needed more than 60% iron to be worth mining. Some with 56 to 59% iron are now mined. Ore from old river channels (pisolitic limonite) is mined at 57 to 59%, and ore eroded from the orebodies has 40 to 55%¹. Magnetite ore is separated with magnets to make a concentrate¹. US resources are mainly low-grade taconite in the Lake Superior district, which must be concentrated and made into pellets before use⁴.

How deposits form

Most of the world’s iron ore is in banded iron formations (BIFs). These are sedimentary rocks with alternating layers of iron minerals and chert, a fine-grained silica rock¹. They were common in the oceans between about 3,800 and 1,800 million years ago³.

About 3,000 million years ago the oceans held little or no dissolved oxygen¹. About 2,500 million years ago, bacteria in the sea began to make oxygen by photosynthesis. The oxygen reacted with iron dissolved in the water, and the iron fell to the sea floor as magnetite and hematite¹. This went on for close to a billion years, until oxygen built up in the air¹.

The ore that is mined is richer than the banded rock around it. The Hamersley Ranges of Western Australia have three main types. These are enriched zones within the BIF (for example Mount Tom Price), iron in ancient river channels, and debris eroded from the orebodies¹.

Where the deposits are

Reserves by country

Australia	31%	27,000 Mt
Brazil	17%	15,000 Mt
Russia	16%	14,000 Mt
Mauritania	5.1%	4,400 Mt
India	3.9%	3,400 Mt
China	3.4%	3,000 Mt
United States	3.1%	2,700 Mt
Canada	2.6%	2,300 Mt
Rest of the world	17%	15,200 Mt

2025. Iron content of reserves. World: 87,000 Mt⁴

Banded iron formations occur on every continent¹. Reserves, as iron content, are in a few countries. The world total in 2025 was 87 billion tonnes. USGS listed Australia with 27 billion tonnes, Brazil with 15 billion and Russia with 14 billion⁴. These three hold about 64% of the total (56,000 ÷ 87,000 million tonnes). Mauritania, India, China, the United States, Canada and Ukraine each hold 2.3 to 4.4 billion tonnes⁴. Geoscience Australia also ranks Australia first in the world for economic resources of iron ore⁵.

In Australia almost 90% of identified iron ore resources are in Western Australia, and almost 80% are in the Hamersley Province of the Pilbara¹. For its older price series, the World Bank used ore from Vale’s Carajás and Itabira mines⁶.

China’s reserves are low in grade. USGS lists 17 billion tonnes of Chinese crude ore with 3 billion tonnes of iron, about 18% iron. Australian reserves are about 46% iron (27 of 59 billion tonnes)⁴.

What it comes with

Iron ore is mined for itself. It is not a by-product of other metals. In 2025 two US companies announced plans to explore for rare-earth elements at iron ore deposits⁴. The river-channel ores of the Pilbara are prized because they are low in impurities such as phosphorus¹.

Sources

1
Geoscience Australia, 2023. Iron (Australian mineral facts) , Properties; Formation; Resources; Mining; Processing.

Ore minerals and their iron content, banded iron formations, Hamersley Province deposit types and grades, processing.
- Iron is not usually found in pure form within rocks, instead it is combined with oxygen in ore minerals
- hematite, Fe 2 O 3 (70% Fe); goethite … (63% Fe); limonite, a mixture of hydrated iron oxides (up to 60% Fe); and magnetite, Fe 3 O 4 (72% Fe)
- The minerals that are mostly used as ore for making iron are hematite
- hematite (from the Greek word meaning ‘blood-stone’)
- until recently most deposits needed to have an average grade of more than 60% iron … some deposits can now have iron grades between 56%-59% iron … Those mined usually contain 57%-59% iron … have a grade of between 40%-55% iron
- Magnetite ore is further processed through magnetic separation
- Most deposits of iron ore in the world are found in rocks known as banded iron formations (BIFs). These are sedimentary rocks that have alternating layers of iron-rich minerals and a fine-grained silica rock called chert
- About 3000 million years ago there was no or very little oxygen dissolved in the oceans
- About 2500 million years ago the oceans were inhabited by bacteria that developed the ability to photosynthesise and produce oxygen … reacted with the soluble iron oxide to form insoluble iron oxide. This precipitated out of solution as the minerals magnetite and hematite
- The process continued for nearly a billion years and eventually let to the accumulation of oxygen in the atmosphere
- there are three main types of iron deposit: iron oxide enrichments within BIFs e.g. Mt Tom Price
- BIFs occur on all continents
- almost 90% of identified resources occur in Western Australia, including almost 80% in the Hamersley Province
- are prized for their low impurities such as phosphorus
2
U.S. Geological Survey, 1956. Iron-ore resources of the United States including Alaska and Puerto Rico, 1955 (Bulletin 1082-C) , Abstract.

Hematite, limonite, magnetite and siderite are the four chief iron-ore minerals. An old source, used only for this mineral fact.
- The four chief iron-ore minerals … siderite
3
Song H., Jiang G., Poulton S.W., Wignall P.B. and others (Nature Communications), 2017. The onset of widespread marine red beds and the evolution of ferruginous oceans , Abstract; Introduction.

Banded iron formations were common about 3.8 to 1.8 billion years ago; their main minerals are hematite, magnetite and siderite.
- siderite (FeCO
- Banded iron formations were a prevalent feature of marine sedimentation ~3.8–1.8 billion years ago
4
U.S. Geological Survey (C.C. Tuck), 2026. Iron Ore, in Mineral Commodity Summaries 2026 , p. 2, World Mine Production and Reserves table; World Resources.

World mine production, reserves and resources of iron ore and its iron content, 2024 and 2025.
- U.S. resources are mainly low-grade taconite-type ores from the Lake Superior district that require beneficiation and agglomeration prior to commercial use
- Australia ... 59,000 ... 27,000 ... Brazil ... 34,000 ... 15,000 ... Russia ... 35,000 ... 14,000
- Australia … 59,000 … 27,000 … Brazil … 34,000 … 15,000 … Russia … 35,000 … 14,000
- 10,000 … 4,400
- Crude ore Iron content … 17,000 … 3,000
- two companies announced plans to explore rare-earth-element extraction at iron ore deposits
5
Geoscience Australia, 2025. World Rankings, in Australia's Identified Mineral Resources 2025 , Table 5, Iron Ore row (as at December 2024).

Australia ranks first for economic resources of iron ore (30% of the world) and first for production (38%) in 2024.
- Iron Ore … 1 … 30%
6
World Bank, 2026. Commodity Price Data (The Pink Sheet), annual and monthly prices , Annual Prices (Nominal), 'Iron ore, cfr spot'; Description sheet; file updated 2 September 2026.

Iron ore price, annual averages 1960 to 2025. Contract price for Brazilian ore in US cents per dry metric tonne unit to 2005, spot price in US dollars per dry tonne after.
- VALE Carajas mines sinter feed, f.o.b. Ponta da Madeira during years 1987-2009; Itabira mines f.o.b. Tubarão for years 1960-86