The water head of water jadeite refers to its transparency, commonly known as "water head". The jade with high transparency is very crystal clear, and it has a feeling of "watery", which is called "watery foot" in jargon, which can better reflect the green color of jade and make it moist and intoxicating. Jade with good water head is alive and its color is dynamic, which is the result of refraction of countless small crystals after light enters the jade. If most of the light can't penetrate the surface of jade, the color of jade appears dull, dull and unattractive, which is called "water shortage" or "dryness" in jargon.