Comparison · Minerals
Chromite vs Magnetite
Chromite and Magnetite are easy to confuse because both are minerals. Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Below is a side-by-side comparison of their properties and the quick tests that separate them.
Key differences between Chromite and Magnetite
- Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Chromite leaves a dark brown to black streak on unglazed porcelain, Magnetite leaves black.
- Both look metallic, so compare color, tarnish and weight rather than shine.
- Magnetite feels noticeably heavier for its size (specific gravity 5.17–5.2 versus 4.5–4.8 for Chromite).
- They overlap in black, but Chromite also comes in brown and Magnetite also comes in gray.
- Well-formed crystals give it away: Chromite is Isometric, Magnetite is Cubic.
Chromite vs Magnetite properties
| Property | Chromite | Magnetite |
|---|---|---|
| Type | Minerals | Minerals |
| Mohs hardness | 5.5 | 5.5–6.5 |
| Luster | Metallic to submetallic | Metallic to submetallic/dull |
| Streak | Dark brown to black | Black |
| Transparency | Opaque | Opaque |
| Specific gravity | 4.5–4.8 | 5.17–5.2 |
| Crystal system | Isometric | Cubic |
| Common colors | Black, Brownish black | Black, Iron-black, Gray-black |
| Rarity | common | common |
| Typical specimen value | $2–$150+ | $2–$150+ |
Which is more valuable?
Typical specimens of Chromite and Magnetite trade in a similar range, around $20.
About Chromite
Chromite is iron chromium oxide, FeCr2O4, a member of the spinel group and the only economically significant ore of chromium. It crystallizes in the cubic system as black to brownish-black grains or octahedral crystals, most often found disseminated through dark, dense mafic and ultramafic rocks. Its formation is closely tied to the early crystallization of magma in large layered igneous intrusions.
About Magnetite
Magnetite is an iron oxide mineral, Fe3O4, crystallizing in the cubic system and the most strongly magnetic naturally occurring mineral on Earth, capable of attracting steel objects and even acting as a natural compass in its lodestone form. It forms in a remarkably wide range of igneous, metamorphic, and sedimentary environments, making it one of the most common accessory minerals in rock-forming systems worldwide. Ancient sailors and travelers used naturally magnetized lodestone, a variety of magnetite, as the earliest known compasses.
Chromite vs Magnetite FAQ
Is Chromite the same as Magnetite?
No. Both are minerals, but they are distinct species with different hardness, streak or luster. Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Chromite from Magnetite?
Both sit near Mohs 5.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Chromite leaves a dark brown to black streak on unglazed porcelain, Magnetite leaves black. Both look metallic, so compare color, tarnish and weight rather than shine.
Which is harder, Chromite or Magnetite?
Magnetite is harder: Mohs 5.5–6.5 against Mohs 5.5 for Chromite.
Which is more valuable, Chromite or Magnetite?
Typical specimens of Chromite and Magnetite trade in a similar range, around $20.
