Comparison · Minerals vs Phosphate Minerals
Kyanite vs Lazulite
Kyanite and Lazulite are easy to confuse. Both sit near Mohs 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 Kyanite and Lazulite
- Both sit near Mohs 5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Kyanite feels noticeably heavier for its size (specific gravity 3.6 versus 3.1 for Lazulite).
- They overlap in blue and green, but Kyanite also comes in orange and black.
- Well-formed crystals give it away: Kyanite is triclinic, Lazulite is monoclinic.
Kyanite vs Lazulite properties
| Property | Kyanite | Lazulite |
|---|---|---|
| Type | Minerals | Phosphate Minerals |
| Mohs hardness | 5 | 5.75 |
| Luster | vitreous | vitreous |
| Streak | White | White |
| Transparency | translucent | translucent |
| Specific gravity | 3.6 | 3.1 |
| Crystal system | triclinic | monoclinic |
| Common colors | Blue, Green, Orange, Black | Blue, Sky blue, Azure blue, Bluish green |
| Rarity | uncommon | rare |
| Typical specimen value | $10–$300+ | $15–$500+ |
Which is more valuable?
Lazulite is usually the more valuable of the two: a typical collector specimen runs about $90 against $50 for Kyanite, and premium Lazulite can reach $500 or more.
About Kyanite
Kyanite is a blue silicate mineral unique for having different hardness values depending on the direction of scratch (4-5 lengthwise, 6-7 crosswise).
About Lazulite
Lazulite is a magnesium aluminum phosphate prized by collectors for its rich azure-blue color. It forms hard pyramidal crystals and granular masses, most often in metamorphic quartzites and pegmatites.
Kyanite vs Lazulite FAQ
Is Kyanite the same as Lazulite?
No. Kyanite is a mineral while Lazulite is a phosphate mineral. Both sit near Mohs 5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Kyanite from Lazulite?
Both sit near Mohs 5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Kyanite feels noticeably heavier for its size (specific gravity 3.6 versus 3.1 for Lazulite). They overlap in blue and green, but Kyanite also comes in orange and black.
Which is harder, Kyanite or Lazulite?
Lazulite is harder: Mohs 5.75 against Mohs 5 for Kyanite.
Which is more valuable, Kyanite or Lazulite?
Lazulite is usually the more valuable of the two: a typical collector specimen runs about $90 against $50 for Kyanite, and premium Lazulite can reach $500 or more.
