Meteorites are fragments of asteroids, the Moon, or Mars that were blasted off the surface during an impact. After a long journey through space, some of these fragments—known as meteoroids—can enter Earth’s atmosphere and reach the ground as meteorites. Although they are very rare, it’s possible to identify a meteorite by looking for certain features—or noticing when they’re missing.
| ⬇ Fusion crust |
| ⬇ Iron and nickel |
| ⬇ Chondrules (tiny spherical grains) |
| ⬇ No internal cavities or “bubbles” |
What is a meteorite?
When a meteoroid enters Earth’s atmosphere at high speed, friction with the air causes its surface to heat up dramatically—sometimes reaching over 2,000 degrees Celsius! This intense heat causes the meteoroid to burn, vaporize, and create a bright streak of light in the sky known as a meteor.
Most meteoroids disintegrate completely in the atmosphere. However, some fragments occasionally survive the journey and reach the ground. These remnants are called meteorites.
Meteorites are made up of rock, silicates, and metals in varying proportions. Most of them come from small asteroids with relatively uniform internal structures. These meteorites are called chondrites, because of the chondrules they contain—tiny spheres made of silicates, magnesium, iron, and glass. These chondrules, often found together with mineral inclusions rich in calcium and aluminum (CAIs), are among the very first solids to have formed in the solar system, around 4.568 billion years ago!
How do you identify a meteorite?
1. Presence of a fusion crust
During atmospheric entry, the intense heat causes the meteorite’s outer surface to melt, forming a thin fusion crust. This crust is usually smooth and shiny, with a glassy appearance and a darker colour than the meteorite’s interior.
This stony meteorite (unclassified NWA) shows a striking example of a fusion crust.
Regmaglypts are visible on its surface. Photo: Espace pour la vie
It is often thin—less than 2 mm thick—and may show cracks or distinctive surface features such as regmaglypts (small thumbprint-like dimples) or flow lines formed by the movement of heated material during atmospheric entry.
If a rock has neither a fusion crust nor metal (such as iron or nickel), it is unlikely to be a meteorite.
2. Presence of iron and nickel
Most meteorites are rich in metal, especially iron and nickel. As a result, they feel heavier than a terrestrial rock of the same size and are magnetic.
The Campo del Cielo meteorite, composed primarily of iron and nickel, is highly magnetic.
Photo: Espace pour la vie
You can test for magnetism using a compass: if the needle responds to the rock's proximity, the sample likely contains metal. A magnet can also be used to check whether the rock is magnetic. However, exposure to a strong magnet may alter the meteorite’s magnetic properties and interfere with scientific analysis.
If a rock has neither a fusion crust nor metal (iron or nickel), it is unlikely to be a meteorite.
3. Presence of chondrules
Chondrules are tiny, millimetre-sized spherical grains that formed in the early solar system. They are found in primitive meteorites known as chondrites.
This slice of the Allende meteorite, discovered in Mexico in 1969, shows numerous chondrules and calcium-aluminum inclusions.
Photo: Espace pour la vie
Chondrules appear as small, spherical grains in a range of colours, sometimes clearly distinct from the rest of the rock. They are often visible to the naked eye or with the help of a magnifying glass. Under a microscope, chondrules reveal complex crystalline structures—evidence of their high-temperature formation in space.
If your sample contains well-defined chondrules, it is probably a chondrite—the most common type of meteorite. However, chondrules are not visible on the surface of fresh meteorites, as the fusion crust hides them. A cut or broken surface is often needed to see them.
4. No internal cavities or “bubbles”
Fewer than 0.1% of meteorites contain internal cavities (or “bubbles”), which are formed by gases during solidification.
Example of basalt (left) and metallurgical slag (center and right) of terrestrial origin.
The presence of numerous surface cavities (or “bubbles”) and the absence of fusion crusts indicate that these are not meteorites.
Photo: Espace pour la vie
These bubbles, which give the rock a vesicular appearance, are actually common in many terrestrial rocks. They occur, for example, in basalt and metallurgical slag. Although they may look unusual, such specimens can be found all over the world.
then it is not a meteorite.
Could it be a meteorite?
The chances of finding a meteorite in nature are extremely low. Fewer than 1%—sometimes as few as 1 in 1,000—of the samples submitted for identification turn out to be actual meteorites.
Many terrestrial rocks, weathered by time, can even resemble freshly fallen meteorites! This isn’t surprising—after all, our planet and meteorites share a common origin, so it’s natural to find many similarities between them.
If your sample appears to match the characteristics of a meteorite, you can fill out the form below. We’ll help you determine whether your rock is of terrestrial origin or if it’s truly a meteorite.
Meteorite identification request
Due to the high volume of requests, we will only respond to submissions that include a detailed description of the find. Fields marked with an asterisk are required.