Grease belt separation relies on which property of diamonds?

Grease belt separation relies on which property of diamonds?

• A. Density
• B. Magnetic properties
• C. Affinity for grease
• D. Color

Answer: (C)

Grease belt separation relies on how a diamond’s surface interacts with hydrocarbon grease. Diamonds have a nonpolar surface that wets well with oil, giving them a strong affinity for grease. When a material moves across a grease-coated belt, diamonds cling to the grease film and ride along with the belt, while other materials that don’t wet as readily don’t adhere as well and separate away. This is a surface-chemistry effect, not about density, magnetism, or color, which is why affinity for grease is the determining property.

Grease belt separation relies on how a diamond’s surface interacts with hydrocarbon grease. Diamonds have a nonpolar surface that wets well with oil, giving them a strong affinity for grease. When a material moves across a grease-coated belt, diamonds cling to the grease film and ride along with the belt, while other materials that don’t wet as readily don’t adhere as well and separate away. This is a surface-chemistry effect, not about density, magnetism, or color, which is why affinity for grease is the determining property.