Which of the following best describes the cleavage of the mineral in this image

Which of the following best describes the cleavage of the mineral in this image? One plane 3 planes at 90

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 2 planes at 90

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 2 planes not at 90

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 No cleavage 3 planes not at 90

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The correct answer and explanation is:

To accurately determine the cleavage of a mineral, we would need to analyze the image, which includes looking at the orientation of planes of weakness in the mineral’s crystal structure. Since I can’t see the image, I’ll describe the cleavage types and explain how to identify them based on the options provided.

The Correct Answer: (Depends on the mineral’s visible cleavage)

Mineral cleavage is described as the tendency of a mineral to break along flat, parallel surfaces, which correspond to zones of weaker bonding in its crystal lattice. Here’s a breakdown of the options:

1. One plane: Minerals with a single cleavage plane, like mica, will break into thin sheets along one direction. Look for a shiny, planar surface.
2. 2 planes at 90°: Minerals like feldspar exhibit cleavage along two planes that intersect at right angles. Look for a blocky appearance with rectangular faces.
3. 2 planes not at 90°: Minerals like amphibole break along two planes that intersect at angles other than 90°, producing a wedge-like structure.
4. 3 planes at 90°: Halite and galena are examples. They break into cubes due to cleavage along three mutually perpendicular planes.
5. 3 planes not at 90°: Calcite cleaves along three planes that intersect at oblique angles, creating rhombohedral shapes.
6. No cleavage: Minerals like quartz lack cleavage and break irregularly, producing a conchoidal fracture.

Explanation of Cleavage:

Cleavage results from the atomic structure of minerals. In minerals with strong covalent bonds, cleavage planes are absent or poorly defined. Conversely, ionic or weaker bonds between planes of atoms result in well-defined cleavage.

To determine cleavage, examine the mineral for repeated, parallel, flat surfaces. The angular relationships between these planes will indicate the type of cleavage. For precise identification, consider both visual observation and physical testing.