What term describes a green or brown patch around the girdle on a cut diamond, typically a blemish but may be an inclusion if it extends into the stone?

What term describes a green or brown patch around the girdle on a cut diamond, typically a blemish but may be an inclusion if it extends into the stone?

• A. Natural Radiation Stain
• B. Near-gem
• C. Needle (Ndl)
• D. Nick (Nk)

Answer: (A)

Discoloration in diamonds that shows up as a green or brown patch around the girdle is described as a natural radiation stain. This occurs when natural radioactivity within the diamond or surrounding materials causes color to form near the surface. On the outside, it appears as a blemish or stain; if that patch extends into the stone, it becomes an inclusion. The other terms correspond to different defects: a needle is a slender crystal inclusion inside the diamond, a nick is a small edge chip on the girdle, and near-gem isn’t a standard term used to describe this feature.

Discoloration in diamonds that shows up as a green or brown patch around the girdle is described as a natural radiation stain. This occurs when natural radioactivity within the diamond or surrounding materials causes color to form near the surface. On the outside, it appears as a blemish or stain; if that patch extends into the stone, it becomes an inclusion. The other terms correspond to different defects: a needle is a slender crystal inclusion inside the diamond, a nick is a small edge chip on the girdle, and near-gem isn’t a standard term used to describe this feature.