he grading and evaluation standards of rubies are mainly based on 1T and 4C: Прозрачность, Цвет, Ясность, Резать, и карат. 1. Прозрачность: 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: прозрачный, полупрозрачный, полупрозрачный, полупрозрачный, and opaque. […]
