Chapter 1.6, Problem 2A

Summary Introduction

a.

To determine:

The number of cleavage surfaces that are present on the specimen.

Introduction:

The crystalline structure of the mineral contains some weaker chemical bonds around which breakage can occur on the application of stress. This property of breakage of minerals around the plane where week bonding is present is known as cleavage.

Summary Introduction

b.

To determine:

The number of directions of cleavage that are present on the specimen.

Introduction:

The direction of cleavage describes the total number of sets of planes that are made on the surface of the mineral at the time of cleavage. When the cleavage surface contains a different orientation, the cleavage is known to have a different direction.

Summary Introduction

c.

To determine:

Whether the direction of cleavage meets at the 90-degree angles or any other angle than 90 degrees.

Introduction:

The angle of cleavage is the point at which the direction of cleavage tends to meet. The angles at which the cleavage commonly occurs are 60, 75, 90, and 120 degrees.