Which one of the following minerals has isolated (SiO$_4$)$^{4-}$ tetrahedra linked by divalent cations in octahedral coordination?
Which one of the following minerals has isolated (SiO$_4$)$^{4-}$ tetrahedra linked by divalent cations in octahedral coordination?
Show Hint
- Muscovite
- Quartz
- Beryl
- Olivine
The Correct Option is D
Solution and Explanation
Step 1: Understanding the question.
The question asks about a mineral that has isolated tetrahedra of SiO$_4$ linked by divalent cations in octahedral coordination. This is characteristic of the mineral olivine.
Step 2: Analyzing the options.
(A) Muscovite: Muscovite is a type of mica, with a different structure from olivine.
(B) Quartz: Quartz consists of SiO$_2$ where the tetrahedra are not isolated, but form a continuous chain or framework.
(C) Beryl: Beryl is a silicate mineral with a hexagonal crystal structure, not isolated tetrahedra.
(D) Olivine: This is the correct answer. Olivine has isolated SiO$_4$ tetrahedra linked by divalent cations in octahedral coordination.
Step 3: Conclusion.
The correct answer is (D) Olivine because it matches the description of the mineral with isolated SiO$_4$ tetrahedra.
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