Which mineral is classified in the orthorhombic crystal system?

Topaz is classified in the orthorhombic crystal system, which is characterized by three mutually perpendicular axes of different lengths. In this system, the symmetry is lower than in cubic or tetragonal systems, but it still retains some degree of regularity and organization in its structure.

Topaz, as an aluminum silicate mineral, typically forms hexagonal or prismatic crystals that exhibit distinct cleavage and a range of hardness due to its crystalline structure. Understanding the crystal systems is essential in identifying and categorizing minerals effectively, as the arrangement of atoms within the crystal lattice directly influences many physical properties.

In contrast, quartz belongs to the hexagonal system, sodalite is cubic, and fluorite crystallizes in the cubic system as well, which highlights the distinctive nature of topaz among the options provided. This classification is crucial for gemologists and mineralogists when determining the characteristics and potential uses of these minerals in various applications.