Comparison · Silicate Minerals
Microcline vs Orthoclase
Microcline and Orthoclase 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 Orthoclase
- Both sit near Mohs 6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- They overlap in pink, but Microcline also comes in white, green, and gray and Orthoclase also comes in clear and yellow.
- Well-formed crystals give it away: Microcline is triclinic, Orthoclase is monoclinic.
Microcline vs Orthoclase properties
| Property | Microcline | Orthoclase |
|---|---|---|
| Type | Silicate Minerals | Silicate Minerals |
| Mohs hardness | 6 | 6 |
| Luster | vitreous | vitreous |
| Streak | White | White |
| Transparency | translucent | translucent |
| Specific gravity | 2.56 | 2.56 |
| Crystal system | triclinic | monoclinic |
| Common colors | White, Cream, Pink, Green, Gray | Colorless, White, Cream, Pink, Yellow |
| Rarity | common | common |
| Typical specimen value | $5–$300+ | $5–$250+ |
Which is more valuable?
Microcline is usually the more valuable of the two: a typical collector specimen runs about $40 against $35 for Orthoclase, and premium Microcline can reach $300 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 Orthoclase
Orthoclase is a common potassium feldspar and a major rock-forming mineral in granitic rocks. It defines hardness 6 on the Mohs scale and appears as cream, pink, or colorless crystals and masses.
Microcline vs Orthoclase FAQ
Is Microcline the same as Orthoclase?
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 Orthoclase?
Both sit near Mohs 6, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. They overlap in pink, but Microcline also comes in white, green, and gray and Orthoclase also comes in clear and yellow. Well-formed crystals give it away: Microcline is triclinic, Orthoclase is monoclinic.
Which is harder, Microcline or Orthoclase?
They are about equally hard, both near Mohs 6.
Which is more valuable, Microcline or Orthoclase?
Microcline is usually the more valuable of the two: a typical collector specimen runs about $40 against $35 for Orthoclase, and premium Microcline can reach $300 or more.
