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)

A natural radiation stain describes discoloration caused by natural irradiation that leaves a green or brown patch around the girdle. This patch is typically a surface blemish, and if it extends into the stone, it would be considered an inclusion. The green/brown patch around the girdle fits this description precisely, which is why it’s identified as a natural radiation stain. Other terms refer to different defects: a needle is an elongated crystal inclusion inside the diamond, a nick is a small edge chip, and “near-gem” isn’t a recognized term for this condition.

A natural radiation stain describes discoloration caused by natural irradiation that leaves a green or brown patch around the girdle. This patch is typically a surface blemish, and if it extends into the stone, it would be considered an inclusion. The green/brown patch around the girdle fits this description precisely, which is why it’s identified as a natural radiation stain. Other terms refer to different defects: a needle is an elongated crystal inclusion inside the diamond, a nick is a small edge chip, and “near-gem” isn’t a recognized term for this condition.