Earth's crust and elements and materials inside

The Earth's crust, a significant part of the planet occupying the surface where humans reside, is primarily composed of eight elements, with oxygen being the most abundant (46.60%), followed by silicon (27.72%), aluminum (8.13%), iron (5.00%), calcium (3.63%), sodium (2.83%), potassium (2.59%), and magnesium (2.09%). The remaining elements make up the remaining 1.41% of the crust. These elements combine to form a wide variety of minerals that contribute to the geological diversity of the crust. Over 2,000 minerals have been identified within the crust, belonging to six major mineral groups. These minerals play a crucial role in the formation and structure of rocks. Each mineral exhibits unique physical characteristics such as external crystal form, cleavage, fracture, lustre, colour, streak, transparency, structure, hardness, and specific gravity. By studying the composition, minerals, and physical characteristics of the Earth's crust, we gain valuable insights into the dynamic processes that have shaped our planet's surface, leading to a deeper understanding of its geological complexity and diversity.

External crystal form:

The arrangement of molecules determines the shape of the crystal, which can be cubes, octahedrons, hexagonal prisms, and more.

Cleavage:

Minerals have a tendency to break along specific directions, producing flat surfaces. The internal arrangement of molecules determines the direction and angle of cleavage.

Fracture:

Some minerals do not have planes of molecules, resulting in irregular breakage patterns.

Lustre:

Each mineral has its own distinct appearance, such as metallic, silky, or glossy.

Colour:

Some minerals have characteristic colours based on their molecular structure, while others are colored by impurities.

Streak:

The colour of a mineral's powdered form may differ from its appearance, and this is known as its streak.

Transparency:

Minerals can be transparent, translucent (light passes through but gets diffused), or opaque (light does not pass through).

Structure:

Minerals can have different arrangements of individual crystals, ranging from fine to coarse-grained or fibrous.

Hardness:

The resistance of a mineral to being scratched is measured on a scale from 1 to 10. For example, talc has a hardness of 1, while diamond has a hardness of 10.

Specific gravity:

This refers to the ratio of an object's weight to the weight of an equal volume of water. It is determined by weighing the object in air and water.

These characteristics provide valuable information for identifying and classifying minerals. Understanding the composition and properties of minerals in the Earth's crust is crucial for various scientific disciplines and practical applications.