Comparison · Minerals vs Borate Minerals
Borax vs Ulexite
Borax and Ulexite are easy to confuse. Both sit near Mohs 2–2.5, 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 Borax and Ulexite
- Both sit near Mohs 2–2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
- Hold a thin edge to the light: Borax is Transparent to translucent, Ulexite is translucent.
- They overlap in clear, but Borax also comes in gray.
- Well-formed crystals give it away: Borax is Monoclinic, Ulexite is triclinic.
Borax vs Ulexite properties
| Property | Borax | Ulexite |
|---|---|---|
| Type | Minerals | Borate Minerals |
| Mohs hardness | 2–2.5 | 2.5 |
| Luster | Vitreous to resinous, earthy when dehydrated | vitreous |
| Streak | White | White |
| Transparency | Transparent to translucent | translucent |
| Specific gravity | 1.7 | 1.95 |
| Crystal system | Monoclinic | triclinic |
| Common colors | White, Colorless, Gray | White, Colorless |
| Rarity | common | uncommon |
| Typical specimen value | $2–$150+ | $5–$120+ |
Which is more valuable?
Ulexite is usually the more valuable of the two: a typical collector specimen runs about $25 against $20 for Borax, and premium Ulexite can reach $120 or more.
About Borax
Borax is a hydrated sodium borate mineral, Na2B4O7·10H2O, that crystallizes from the evaporation of alkaline lakes in arid basins. It has been mined and used by humans for thousands of years as a cleaning agent, flux, and preservative, making it one of the more historically significant evaporite minerals. Borax dissolves readily in water and gives off a sweetish alkaline taste, reflecting its high solubility compared to most rock-forming minerals.
About Ulexite
Ulexite is a hydrated sodium calcium borate best known for its fibrous variety, which transmits light along its fibers. Sliced and polished plates project an image from the back surface, earning it the nickname television stone.
Borax vs Ulexite FAQ
Is Borax the same as Ulexite?
No. Borax is a mineral while Ulexite is a borate mineral. Both sit near Mohs 2–2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Borax from Ulexite?
Both sit near Mohs 2–2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Hold a thin edge to the light: Borax is Transparent to translucent, Ulexite is translucent. They overlap in clear, but Borax also comes in gray.
Which is harder, Borax or Ulexite?
They are about equally hard, both near Mohs 2–2.5.
Which is more valuable, Borax or Ulexite?
Ulexite is usually the more valuable of the two: a typical collector specimen runs about $25 against $20 for Borax, and premium Ulexite can reach $120 or more.
