1. Features: The true scientific research certificate is printed with the aurora symbol, and the true comprehensive scientific research certificate is printed with the five-dimensional holographic structure symbol.

2. Evaluation criteria: The evaluation criteria of true scientific research certificate mainly focus on the quality of pearls, including luster, transparency, shape and size, while the evaluation criteria of true comprehensive research certificate pay more attention to the comprehensive evaluation of pearls, including thickness, compactness and flatness.