Comparison · Feldspar Group vs Metamorphic Rocks
Feldspar vs Unakite
Feldspar and Unakite are easy to confuse. Both sit near Mohs 6–6.5, 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 Feldspar and Unakite
- Both sit near Mohs 6–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Streak color differs: Feldspar leaves a white streak on unglazed porcelain, Unakite leaves variable; test individual minerals.
- Hold a thin edge to the light: Feldspar is Transparent to translucent, Unakite is opaque.
- They overlap in pink and green, but Feldspar also comes in gray and clear and Unakite also comes in multicolored.
Feldspar vs Unakite properties
| Property | Feldspar | Unakite |
|---|---|---|
| Type | Feldspar Group | Metamorphic Rocks |
| Mohs hardness | 6–6.5 | 6.5 |
| Luster | Vitreous to pearly | vitreous |
| Streak | White | Variable; test individual minerals |
| Transparency | Transparent to translucent | opaque |
| Specific gravity | 2.55–2.76 | 2.9 |
| Crystal system | Monoclinic to Triclinic (depending on species) | varies |
| Common colors | White, Pink, Gray, Green (amazonite), Colorless | Pink and Green mottled, Salmon, Olive Green |
| Rarity | common | common |
| Typical specimen value | $2–$150+ | $2–$50+ |
Which is more valuable?
Feldspar is usually the more valuable of the two: a typical collector specimen runs about $20 against $10 for Unakite, and premium Feldspar can reach $150 or more.
About Feldspar
Feldspar is not a single mineral but a group of related aluminosilicate minerals, comprising the potassium feldspars, orthoclase, microcline, and sanidine, and the plagioclase series running from albite to anorthite, together making up roughly 60 percent of Earth's crust by volume. All share a similar framework silicate structure, two cleavage directions near 90 degrees, and moderate hardness, but differ in composition, color, and crystal system. As the most abundant mineral group on the planet, feldspar defines granite, basalt, gneiss, and countless other rock types.
About Unakite
Unakite is a metamorphosed granite composed of pink orthoclase feldspar, green epidote, and quartz. Named after the Unaka Mountains of Tennessee.
Feldspar vs Unakite FAQ
Is Feldspar the same as Unakite?
No. Feldspar is a feldspar group while Unakite is a metamorphic rock. Both sit near Mohs 6–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Feldspar from Unakite?
Both sit near Mohs 6–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Streak color differs: Feldspar leaves a white streak on unglazed porcelain, Unakite leaves variable; test individual minerals. Hold a thin edge to the light: Feldspar is Transparent to translucent, Unakite is opaque.
Which is harder, Feldspar or Unakite?
They are about equally hard, both near Mohs 6–6.5.
Which is more valuable, Feldspar or Unakite?
Feldspar is usually the more valuable of the two: a typical collector specimen runs about $20 against $10 for Unakite, and premium Feldspar can reach $150 or more.
