Certainly! Here are the physical properties of the minerals you specified:
1. Pyroxene
- Composition: Silicate mineral, typically containing calcium, magnesium, iron, and aluminum.
- Luster: Vitreous to dull.
- Colour: Typically dark green, black, or brown.
- Streak: White to colorless.
- Hardness: 5 to 7 on Mohs scale.
- Cleavage or Fracture: Cleavage in two directions at nearly 90 degrees; uneven fracture.
2. Pyrite
- Composition: Iron sulfide (FeS₂).
- Luster: Metallic.
- Colour: Brass-yellow (often referred to as "fool's gold").
- Streak: Greenish-black to brownish-black.
- Hardness: 6 to 6.5 on Mohs scale.
- Cleavage or Fracture: No true cleavage; conchoidal fracture.
3. Dioptase
- Composition: Hydrated copper silicate (CuSiO₃·H₂O).
- Luster: Vitreous.
- Colour: Bright green to blue-green.
- Streak: Green.
- Hardness: 5 to 5.5 on Mohs scale.
- Cleavage or Fracture: Perfect cleavage in one direction; conchoidal fracture.
4. Hematite
- Composition: Iron oxide (Fe₂O₃).
- Luster: Metallic to dull.
- Colour: Often reddish-brown or silver-gray.
- Streak: Reddish-brown.
- Hardness: 5 to 6 on Mohs scale.
- Cleavage or Fracture: No cleavage; uneven to sub-conchoidal fracture.
5. Magnetite
- Composition: Iron oxide (Fe₃O₄).
- Luster: Metallic.
- Colour: Black or steel-gray.
- Streak: Black.
- Hardness: 5.5 to 6.5 on Mohs scale.
- Cleavage or Fracture: No cleavage; uneven fracture.
6. Biotite
- Composition: Silicate mineral; a member of the mica group, with potassium, magnesium, iron, and aluminum.
- Luster: Vitreous to pearly.
- Colour: Dark brown to black, often with a bronze tint.
- Streak: White to pale brown.
- Hardness: 2.5 to 3 on Mohs scale.
- Cleavage or Fracture: Perfect cleavage in one direction, resulting in thin flexible sheets.
These properties provide useful information for the identification and classification of these commonly encountered minerals.
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