Magnetite reacts with oxygen in ways that produce hematite.
Hematite is the fully oxidized end-product of magnetite.
So, in many ways they are very similar.
Hematite and magnetite are both equally essential oxides of iron.
However, there are a few differences between them.
The important difference between hematite and magnetite is that the iron in hematite is in +3 oxidation state, whereas in magnetite it is in +2 and +3 oxidation states.
The remainder of this article will give you an in depth look at both hematite and magnetite, what they look like, where they came from and what they are used for.
Hematite vs Magnetite (EXPLAINED)
The name hematite means “blood” in Greek, due to the intense red pigmentation found in certain varieties of this mineral.
This beautiful rock has an extremely variable appearance and can naturally occur in bright black, silver-gray, rustic-brown, or a variety of red hues.
People have been using Hematite iron oxide throughout human history as a source of red pigment, paint, and dye in its powdered form for thousands of years.
Pictograph writings of this red chalk mineral from 165,000 years ago are one of the earliest in mankind’s history.
Hematite is a dense, beautiful, and inexpensive material with an earthy to metallic luster.
Polished bright hematite is widely known as a gemstone and is popular among jewelry making materials.
Hematite was also known to be worn as mourning jewelry, believed to be a connection to the deceased.
However, people are usually surprised to see a shiny silver-colored mineral produce a reddish streak when scraped or eroded.
One may quickly learn that the red streak is the most important clue for identifying real hematite and separating it from similar looking minerals such as magnetite.
Hematite gets its intense red color from oxidized iron and magnetic interactions.
Hematite has a wide variety of purposes, but no economic significance is greater than the importance of its iron ore (Fe2O3).
This is because of hematite’s 70 percent iron content, with its remaining 30 percent being oxygen.
This rock-forming mineral is one of the most plentiful on Earth’s surface and along the crust.
Variations of hematite include; Hematite rose, Kidney ore, Tiger iron, Specularite, and Oolitic hematite.
Thanks to NASA’s exploration rovers, it can also be discovered in abundance within the Martian rocks and soils on Mars’ crust, giving the planet its reddish-brown terrain.
Magnetite is seen as a metallic to dull luster, black in color, and its streak is black.
It is also a mineral and one of the two main oxides of iron ore, with the chemical formula Fe3O4.
Magnetite’s greatest use is being an important iron ore in steel manufacturing.
As its name implies, magnetite is magnetic, and this inherently magnetic iron-containing mineral is described as ferrimagnetic.
It is not only attracted to a magnet but can be magnetized to become a permanent magnet all on its own.
It is the most magnetic of all the naturally occurring minerals known to man. In high enough volumes, magnetite can even alter compass navigation.
In Tasmania, where these highly magnetized rocks are abundant, there are many areas that can greatly influence compasses.
Research at the University of North Carolina also concluded that salmon are guided by magnetite’s magnetic field to return to the rivers where they were birthed.
Further, it is an insoluable material, so it is also used in water purification.
Interestingly, living organisms can singly produce magnetite inside their bodies.
In humans and animals, iron can be found in three forms in the brain – magnetite, hemoglobin or blood and ferritin (protein).
Magnetite can be found in several different parts of the brain, including the frontal, brainstem, and cerebellum.
Similarities and Differences
The most abundant hematite and magnetite deposits found on earth formed in sedimentary environments just over two billion years ago when the earth’s oceans were rich in broken-down iron.
Photosynthesis began happening in much of the ocean, and vast deposits of hematite began collecting on the seafloor.
This distinctive downfall continued for more than one hundred million years.
This allowed for the continuous evolution of banded alternating layers of iron deposits thousands of feet in depth.
These deposits laterally stretched over thousands of square miles at locations throughout the world.
They encompass some of the largest rock formations on Earth’s rock record.
Some magnetite specifically eroded from rocks, then was carried to the beach by rivers and is sometimes found in large concentrations in beach sand.
Almost all sedimentary iron deposits contain hematite and magnetite along with other minerals.
These materials are often in close association though both contain iron in different oxidation states.
Magnetite holds a higher content of iron and is easier to process, but hematite is leading in iron ore production because it is more abundant.
Thus, massive amounts of hematite are mined each year.
Although it was once mined at hundreds of locations spanning most parts of the world.
Due to depletion, today, hematite is mined in just a few of the largest mines.
Most ore is now produced at the world’s largest iron mine in Northern Brazil, which holds over 7 billion tons of reserves.
How The Two Can Be Confused
Hematite is an iron oxide with the chemical formula Fe2O3; magnetite is also an iron oxide but with the chemical formula Fe3O4.
Another important difference between hematite and magnetite is that hematite appears in a variety of colors, but magnetite is only black in color.
Hematite makes a rust or blood-red colored streak; magnetite makes a black or dark gray streak.
The amount of hematite on the surface of the Earth and other oxidizing atmospheric planets, notably Mars, far exceeds that of magnetite, but hematite is not dominant magnetically.
Despite the fact that hematite contains iron, unlike magnetite, it has an extremely weak or nonexistent magnetic field, and it is not noticeably attracted to your average magnet.
This is because of the presence of a small percentage of other chemicals and elements which alter the magnetic properties and electronic configuration of the way their atoms align.
However, because both minerals formed in the same environments, some specimens of hematite contain enough magnetite that they can be attracted to a magnet.
This can lead to an incorrect conclusion that the hematite specimen is magnetite.
Therefore, it is important to check other properties such as the red and black streak test to make a proper identification.