In grading, what is the role of environmental control?

• A. Keep lighting as daylight-equivalent and balanced as possible
• B. Use multiple conflicting light sources
• C. Avoid any standardized lighting
• D. Only use colored lighting

Answer: (A)

In grading, environmental control centers on offering neutral, daylight-equivalent lighting so color and clarity are judged under consistent, objective viewing conditions. Daylight-equivalent illumination with a balanced spectrum minimizes color casts and shadows, helping the grader see the stone as it would appear in typical daylight and enabling reliable, repeatable assessments. Using multiple conflicting light sources would create uneven color balance and shadows, making judgments inconsistent. Skipping standardized lighting removes reproducibility, and colored lighting would distort color perception altogether. With proper environmental control, grading results are consistent and comparable across stones and graders.