Comparison · Minerals
Augite vs Hornblende
Augite and Hornblende are easy to confuse because both are minerals. Both sit near Mohs 5.5–6, 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 Augite and Hornblende
- Both sit near Mohs 5.5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Augite leaves a grayish green to colorless streak on unglazed porcelain, Hornblende leaves pale gray to colorless.
Augite vs Hornblende properties
| Property | Augite | Hornblende |
|---|---|---|
| Type | Minerals | Minerals |
| Mohs hardness | 5.5–6 | 5–6 |
| Luster | Vitreous to resinous | Vitreous to silky |
| Streak | Grayish green to colorless | Pale gray to colorless |
| Transparency | Translucent to opaque | Translucent to opaque |
| Specific gravity | 3.2–3.6 | 3.0–3.4 |
| Crystal system | Monoclinic | Monoclinic |
| Common colors | Black, Dark green, Brown | Black, Dark green, Dark brown |
| Rarity | common | common |
| Typical specimen value | $2–$150+ | $2–$150+ |
Which is more valuable?
Typical specimens of Augite and Hornblende trade in a similar range, around $20.
About Augite
Augite is a common rock-forming pyroxene, a calcium-magnesium-iron silicate with the general formula (Ca,Mg,Fe)2Si2O6, and one of the most abundant dark minerals in basalt and gabbro. It crystallizes in the monoclinic system and typically appears as stubby black to greenish-black prisms with a characteristic near-right-angle cleavage. Augite is a rock-forming mineral rather than a gem material, valued mainly by collectors for its well-formed crystals.
About Hornblende
Hornblende is the most common member of the amphibole mineral group, a complex calcium-iron-magnesium aluminosilicate that forms dark, elongated prismatic crystals in a wide variety of igneous and metamorphic rocks. It typically appears black to dark green and is easily recognized by a characteristic cleavage angle of about 56 and 124 degrees. Hornblende is a rock-forming mineral rather than a gem, though well-formed crystals are collected for their sharp form.
Augite vs Hornblende FAQ
Is Augite the same as Hornblende?
No. Both are minerals, but they are distinct species with different hardness, streak or luster. Both sit near Mohs 5.5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Augite from Hornblende?
Both sit near Mohs 5.5–6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Augite leaves a grayish green to colorless streak on unglazed porcelain, Hornblende leaves pale gray to colorless.
Which is harder, Augite or Hornblende?
They are about equally hard, both near Mohs 5.5–6.
Which is more valuable, Augite or Hornblende?
Typical specimens of Augite and Hornblende trade in a similar range, around $20.
