Comparison · Silicate Minerals
Microcline vs Prehnite
Microcline and Prehnite are easy to confuse because both are silicate minerals. Both sit near Mohs 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 Microcline and Prehnite
- Both sit near Mohs 6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- They overlap in white, green, and gray, but Microcline also comes in pink and Prehnite also comes in yellow.
- Well-formed crystals give it away: Microcline is triclinic, Prehnite is orthorhombic.
Microcline vs Prehnite properties
| Property | Microcline | Prehnite |
|---|---|---|
| Type | Silicate Minerals | Silicate Minerals |
| Mohs hardness | 6 | 6.25 |
| Luster | vitreous | vitreous |
| Streak | White | White |
| Transparency | translucent | translucent |
| Specific gravity | 2.56 | 2.88 |
| Crystal system | triclinic | orthorhombic |
| Common colors | White, Cream, Pink, Green, Gray | Green, Yellow-green, Yellow, White, Gray |
| Rarity | common | uncommon |
| Typical specimen value | $5–$300+ | $10–$400+ |
Which is more valuable?
Prehnite is usually the more valuable of the two: a typical collector specimen runs about $70 against $40 for Microcline, and premium Prehnite can reach $400 or more.
About Microcline
Microcline is a potassium-rich feldspar and a rock-forming mineral in granites and pegmatites. Its blue-green gem variety, amazonite, is widely collected, while ordinary microcline appears as cream, pink, or gray crystals and masses.
About Prehnite
Prehnite is a calcium aluminum silicate best known for its soft green to yellow-green color and rounded, botryoidal crystal aggregates. It commonly lines cavities in basalt and is valued by collectors and lapidaries for its translucent glow.
Microcline vs Prehnite FAQ
Is Microcline the same as Prehnite?
No. Both are silicate minerals, but they are distinct species with different hardness, streak or luster. Both sit near Mohs 6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Microcline from Prehnite?
Both sit near Mohs 6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. They overlap in white, green, and gray, but Microcline also comes in pink and Prehnite also comes in yellow. Well-formed crystals give it away: Microcline is triclinic, Prehnite is orthorhombic.
Which is harder, Microcline or Prehnite?
They are about equally hard, both near Mohs 6.
Which is more valuable, Microcline or Prehnite?
Prehnite is usually the more valuable of the two: a typical collector specimen runs about $70 against $40 for Microcline, and premium Prehnite can reach $400 or more.
