Black nephrite is a common type of jade found in Xinjiang. Its color is darker than that of dianmo (speckled ink) and jumo (gathered ink), so it is also called black ink jade, but essentially it is still green nephrite. Due to its superior quality being pitch black, it is easily confused with the full-ink traditional ink jade. The full-ink jade with a celadon base can also be easily mistaken for black nephrite. Personally, I think the key to distinguishing them is by shining a strong light into the jade. In the celadon-based ink jade, one can see uniformly dense ink spots, while in black nephrite, one can see ink clusters resembling seaweed. In traditional ink jade, when strong light is shone directly and vertically onto the jade surface, a transparent layer of jade quality like thin plastic film can be seen between the light layer and the ink substance layer. In terms of texture, the full-ink jade with a celadon base feels glutinous, soft, and flexible, whereas black nephrite...