What is the finest-quality jadeite referred to as?

The term that refers to the finest-quality jadeite is "Imperial jade." This classification is highly regarded in the gemstone market due to its exceptional quality, which includes a vivid green color, translucency, and a smooth texture. Imperial jade specifically denotes jadeite that is of the highest purity and has a rich, deep green hue, often with no visible inclusions. It is the most sought-after and valuable type of jade due to these characteristics, making it a prized possession among collectors and enthusiasts.

In contrast, other terms such as "Premium jade," "Royal jade," and "Exquisite jade" do not have the same recognized status or definition in the industry. While they may imply high quality, none specifically denote the top-tier quality that is emblematic of Imperial jade, which has established standards and characteristics that are widely accepted and understood in the gemological community.