Hundreds of 'Rock Crystals' Found From a 6000-Yr-Old Site Indicate Quartz Fragments Were Used to Decorate Graves The burial practices of ancient populations have always intrigued researchers because ...

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 ...

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 ...