What trait is highlighted by naming a diamond as the gem?

• A. Stands up under pressure
• B. Glows in the dark
• C. Changes color with temperature
• D. Is cheap

Answer: (A)

Diamonds are celebrated for their ability to endure, so the trait being highlighted is durability under pressure. This comes from its exceptional hardness—the hardest natural material on the Mohs scale—and a tightly bound crystal lattice of strong covalent bonds that lets it resist scratching and maintain its shape under heavy forces. That resilience under compression is what people “name” when they think of it as the gem, signaling its lasting strength. The other options don’t fit as well: glowing in the dark isn’t a universal, defining feature of diamonds (some fluoresce under certain lights, but it’s not a standard trait); changing color with temperature isn’t typical for diamonds; and diamonds are not cheap, which contradicts the common perception of their value.