Which statement best describes the relationship between isometric and cubic crystal systems in diamonds?

Which statement best describes the relationship between isometric and cubic crystal systems in diamonds?

• A. Cubic is a subset of hexagonal systems
• B. Isometric and Cubic are used interchangeably for diamonds
• C. Diamonds belong to tetragonal system
• D. Monoclinic is the correct system for diamonds

Answer: (B)

Isometric and cubic describe the same high-symmetry crystal arrangement. In diamonds, the lattice is cubic, and historically the term isometric has been used to refer to this same system. So these two terms are effectively interchangeable when describing diamond’s crystal structure, which is why diamonds are described as belonging to the cubic (isometric) system. Other statements don’t fit: diamonds are not in a tetragonal or monoclinic system, and the cubic system is not a subset of hexagonal. The key idea is that isometric equals cubic in this context, reflecting the same symmetry with three equal, perpendicular axes.

Isometric and cubic describe the same high-symmetry crystal arrangement. In diamonds, the lattice is cubic, and historically the term isometric has been used to refer to this same system. So these two terms are effectively interchangeable when describing diamond’s crystal structure, which is why diamonds are described as belonging to the cubic (isometric) system.

Other statements don’t fit: diamonds are not in a tetragonal or monoclinic system, and the cubic system is not a subset of hexagonal. The key idea is that isometric equals cubic in this context, reflecting the same symmetry with three equal, perpendicular axes.