Here's why:
* Crystal structure is a defining characteristic of a mineral. It refers to the specific arrangement of atoms within the mineral. This arrangement dictates many of the mineral's properties, like hardness, cleavage, and even color.
* Different minerals have different crystal structures. For example, diamond and graphite are both made of pure carbon, but they have very different crystal structures. This difference leads to their vastly different properties: diamond is incredibly hard, while graphite is soft and flaky.
* Even within the same mineral species, different pieces can have different crystal structures. This is due to factors like the conditions under which the mineral formed (temperature, pressure, presence of impurities).
Think of it like this: Imagine building a structure with LEGO bricks. You can build a tower, a house, or a car, all using the same LEGO bricks. The final structure (the crystal structure) is determined by how the bricks (the atoms) are arranged.
Therefore, while some pieces of the same mineral might have similar crystal structures, they don't necessarily have to be identical.
