To accurately judge the brilliance of a gemstone, one should view it:

To accurately judge the brilliance of a gemstone, viewing it face-up is essential. This position allows the observer to see the gemstone as it is intended to be displayed, showcasing how light interacts with its facets from the optimal angle. The face-up view provides a clear perspective of how effectively the stone reflects and refracts light, contributing to its overall brightness and color.

When a gemstone is viewed face-up, it offers the best opportunity to appreciate its sparkle, fire, and overall visual appeal. This perspective is crucial in determining the quality of cut, which directly impacts the gemstone's brilliance. Factors like symmetry, proportions, and facet arrangement can also be better evaluated in this position.

Other methods, such as viewing from the side or under a microscope, may provide insights into specific attributes of the gemstone, such as clarity or inclusions, but they do not allow for a comprehensive assessment of brilliance. Natural light can enhance the viewing experience, but again, the face-up orientation is what truly reveals how the gemstone performs in terms of brilliance and visual impact.