Comparison · Feldspar Group vs Silicate Minerals
Feldspar vs Scapolite
Feldspar and Scapolite 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 Scapolite
- Both sit near Mohs 6–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Hold a thin edge to the light: Feldspar is Transparent to translucent, Scapolite is transparent.
- They overlap in pink and gray, but Feldspar also comes in green and clear and Scapolite also comes in white, purple, and yellow.
- Well-formed crystals give it away: Feldspar is Monoclinic to Triclinic (depending on species), Scapolite is tetragonal.
Feldspar vs Scapolite properties
| Property | Feldspar | Scapolite |
|---|---|---|
| Type | Feldspar Group | Silicate Minerals |
| Mohs hardness | 6–6.5 | 6 |
| Luster | Vitreous to pearly | vitreous |
| Streak | White | White |
| Transparency | Transparent to translucent | transparent |
| Specific gravity | 2.55–2.76 | 2.65 |
| Crystal system | Monoclinic to Triclinic (depending on species) | tetragonal |
| Common colors | White, Pink, Gray, Green (amazonite), Colorless | White, Pink, Violet, Yellow, Gray |
| Rarity | common | uncommon |
| Typical specimen value | $2–$150+ | $10–$500+ |
Which is more valuable?
Scapolite is usually the more valuable of the two: a typical collector specimen runs about $70 against $20 for Feldspar, and premium Scapolite can reach $500 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 Scapolite
Scapolite is a group of tectosilicate minerals forming a solid solution between sodium-rich marialite and calcium-rich meionite. It occurs as prismatic crystals or massive material in white, pink, violet, and yellow tones, sometimes showing a cat's-eye effect when cut.
Feldspar vs Scapolite FAQ
Is Feldspar the same as Scapolite?
No. Feldspar is a feldspar group while Scapolite is a silicate mineral. 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 Scapolite?
Both sit near Mohs 6–6.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Hold a thin edge to the light: Feldspar is Transparent to translucent, Scapolite is transparent. They overlap in pink and gray, but Feldspar also comes in green and clear and Scapolite also comes in white, purple, and yellow.
Which is harder, Feldspar or Scapolite?
They are about equally hard, both near Mohs 6–6.5.
Which is more valuable, Feldspar or Scapolite?
Scapolite is usually the more valuable of the two: a typical collector specimen runs about $70 against $20 for Feldspar, and premium Scapolite can reach $500 or more.
