Comparison · Minerals vs Feldspar Group
Diaspore vs Feldspar
Diaspore and Feldspar are easy to confuse. Both sit near Mohs 6.5–7, 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 Diaspore and Feldspar
- Both sit near Mohs 6.5–7, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Diaspore feels noticeably heavier for its size (specific gravity 3.3–3.5 versus 2.55–2.76 for Feldspar).
- They overlap in clear, gray, green, and pink, but Diaspore also comes in yellow, brown, and purple.
- Well-formed crystals give it away: Diaspore is Orthorhombic, Feldspar is Monoclinic to Triclinic (depending on species).
Diaspore vs Feldspar properties
| Property | Diaspore | Feldspar |
|---|---|---|
| Type | Minerals | Feldspar Group |
| Mohs hardness | 6.5–7 | 6–6.5 |
| Luster | Vitreous to pearly on cleavage | Vitreous to pearly |
| Streak | White | White |
| Transparency | Transparent to translucent | Transparent to translucent |
| Specific gravity | 3.3–3.5 | 2.55–2.76 |
| Crystal system | Orthorhombic | Monoclinic to Triclinic (depending on species) |
| Common colors | Colorless, White, Gray, Yellowish, Brown, Green, Violet-pink (color-change) | White, Pink, Gray, Green (amazonite), Colorless |
| Rarity | common | common |
| Typical specimen value | $2–$150+ | $2–$150+ |
Which is more valuable?
Typical specimens of Diaspore and Feldspar trade in a similar range, around $20.
About Diaspore
Diaspore is aluminum oxide hydroxide, AlO(OH), a hard, dense mineral that forms in aluminum-rich metamorphic and hydrothermal environments and ranks among the principal minerals in bauxite ore. It is dimorphous with boehmite, sharing an identical chemical formula but a different crystal structure, and it characteristically splits apart with a sudden crackling sound when heated, a property that inspired its name. Transparent gem-quality crystals, sold as zultanite or csarite, display a striking color change from green to pink or champagne under different lighting.
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.
Diaspore vs Feldspar FAQ
Is Diaspore the same as Feldspar?
No. Diaspore is a mineral while Feldspar is a feldspar group. Both sit near Mohs 6.5–7, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Diaspore from Feldspar?
Both sit near Mohs 6.5–7, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Diaspore feels noticeably heavier for its size (specific gravity 3.3–3.5 versus 2.55–2.76 for Feldspar). They overlap in clear, gray, green, and pink, but Diaspore also comes in yellow, brown, and purple.
Which is harder, Diaspore or Feldspar?
Diaspore is harder: Mohs 6.5–7 against Mohs 6–6.5 for Feldspar.
Which is more valuable, Diaspore or Feldspar?
Typical specimens of Diaspore and Feldspar trade in a similar range, around $20.
