he grading and evaluation standards of rubies are mainly based on 1T and 4C: Transparenţă, Culoare, Claritate, Tăiat, și Carat. 1. Transparenţă: refers to the degree to which a gemstone allows visible light to pass through. In the visual identification of rubies, transparency is generally divided into five levels: transparent, translucid, translucid, subtranslucid, și opace. [...]
