Among the following, the mineral showing acicular habit is
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- kyanite
- tourmaline
- biotite
- sillimanite
The Correct Option is D
Solution and Explanation
The mineral showing an acicular habit among the given options is sillimanite.
- Understanding Acicular Habit:
"Acicular" refers to a needle-like crystal form. Minerals with an acicular habit usually consist of slender, needle-like crystals. - Analysis of Options:
- Kyanite: Characterized by a bladed habit, forming flat, blade-like crystals. Not acicular.
- Tourmaline: Typically forms in elongated columns or prisms but not known for a distinctly acicular habit.
- Biotite: Known for a platy or sheet-like habit due to its mica structure. Not acicular.
- Sillimanite: Often forms slender, elongated, needle-like crystals, which perfectly fits the definition of acicular habit.
- Conclusion:
Among the options provided, only sillimanite shows a clear acicular habit by exhibiting needle-like, elongated crystals. Therefore, the correct answer is sillimanite.
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