Which term refers to minerals formed with diamonds at great depths and brought to the surface by the same kimberlites or lamproites?

Which term refers to minerals formed with diamonds at great depths and brought to the surface by the same kimberlites or lamproites?

• A. Industrial rough
• B. Improvables
• C. Habit
• D. Indicator minerals

Answer: (D)

Indicator minerals are minerals that crystallize at mantle depths and are carried to the surface by the same kimberlite or lamproite magmas that transport diamonds. Their presence signals a nearby diamond-bearing source because they share the same formation environment and journey to the surface. In exploration, finding these minerals—such as specific garnets, chromian spinel, or diopside—helps geologists trace back to the original pipe even if diamonds aren’t directly found in every sampled rock. Other terms don’t fit this context. Industrial rough refers to diamonds used for industrial purposes, not minerals that indicate diamond sources. Habit describes a mineral’s external crystal shape, not its role as a tracer for diamond-bearing rocks. Improvables isn’t a standard term in this geological setting.

Indicator minerals are minerals that crystallize at mantle depths and are carried to the surface by the same kimberlite or lamproite magmas that transport diamonds. Their presence signals a nearby diamond-bearing source because they share the same formation environment and journey to the surface. In exploration, finding these minerals—such as specific garnets, chromian spinel, or diopside—helps geologists trace back to the original pipe even if diamonds aren’t directly found in every sampled rock.

Other terms don’t fit this context. Industrial rough refers to diamonds used for industrial purposes, not minerals that indicate diamond sources. Habit describes a mineral’s external crystal shape, not its role as a tracer for diamond-bearing rocks. Improvables isn’t a standard term in this geological setting.