Comparison · Hydroxide Minerals vs Minerals
Brucite vs Calcite
Brucite and Calcite are easy to confuse. Both sit near Mohs 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 Brucite and Calcite
- Both sit near Mohs 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: Brucite is translucent, Calcite is transparent.
- They overlap in green, blue, and yellow, but Brucite also comes in white and gray and Calcite also comes in clear, orange, and pink.
Brucite vs Calcite properties
| Property | Brucite | Calcite |
|---|---|---|
| Type | Hydroxide Minerals | Minerals |
| Mohs hardness | 2.5 | 3 |
| Luster | vitreous | vitreous |
| Streak | White | White |
| Transparency | translucent | transparent |
| Specific gravity | 2.4 | 2.7 |
| Crystal system | trigonal | trigonal |
| Common colors | White, Pale green, Pale blue, Yellow, Gray | Colorless, White, Yellow, Orange, Blue, Green, Pink |
| Rarity | uncommon | common |
| Typical specimen value | $5–$250+ | $2–$100+ |
Which is more valuable?
Brucite is usually the more valuable of the two: a typical collector specimen runs about $40 against $15 for Calcite, and premium Brucite can reach $250 or more.
About Brucite
Brucite is a soft magnesium hydroxide mineral that forms platy, foliated, or fibrous masses with a pearly to vitreous luster. It is usually white but can be pale green, blue, or yellow, and is a notable ore of magnesium.
About Calcite
Calcite is one of the most common minerals on Earth, found in sedimentary, metamorphic, and igneous rocks. It's the primary component of limestone and marble.
Brucite vs Calcite FAQ
Is Brucite the same as Calcite?
No. Brucite is a hydroxide mineral while Calcite is a mineral. Both sit near Mohs 2.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead.
How can you tell Brucite from Calcite?
Both sit near Mohs 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: Brucite is translucent, Calcite is transparent. They overlap in green, blue, and yellow, but Brucite also comes in white and gray and Calcite also comes in clear, orange, and pink.
Which is harder, Brucite or Calcite?
Calcite is harder: Mohs 3 against Mohs 2.5 for Brucite.
Which is more valuable, Brucite or Calcite?
Brucite is usually the more valuable of the two: a typical collector specimen runs about $40 against $15 for Calcite, and premium Brucite can reach $250 or more.
