In the first place he considered the question of the origin in crystalline rocks of the material, and described those peculiarities in external form and internal structure, which would enable us ...

This massive, exposed crystalline rock formed over 2.5 billion years ago, stretches across much of Ukraine. It represents one of Earth’s oldest and most stable continental blocks. The formation ...

These rocks are formed when magma solidifies. As the magma cools, mineral crystals will begin to grow. These crystals will grow and interlock to form a hard crystalline rock. Basalt is usually ...