What Do Cotton, Cracks and Water Lines Mean in Jade?
Cotton, cracks, water lines and colour bands: what jade flaws look like, which ones matter, and how to read them honestly before buying.
Natural jade is rarely flawless, and its internal character has a vocabulary of its own: cotton, cracks, water lines, colour bands. Some of these are harmless personality; others are structural warnings. Knowing which is which keeps buying honest.
Cotton, the cosmetic cloud
Cotton (mian) is the soft white cloudiness inside nephrite — areas of looser fibre structure. It is cosmetic, not structural: the stone is not weaker where cotton appears, only less transparent.
Small, scattered cotton is normal and accepted. Large dense patches lower the price because they dull the stone\u2019s life, but they are a matter of taste rather than safety.
Cracks and stone lines
A crack (lie) is a break in the stone\u2019s structure — a real risk, especially in a bangle that will be worn and knocked. A stone line or vein (liu) may look similar but is a healed or natural boundary that does not threaten the piece.
Only experience and, ideally, a seller\u2019s honest description can reliably separate them. Always ask explicitly: "Are there any cracks in this piece?" and get the answer in writing.
Water lines and colour bands
A water line is a pale, translucent streak through the stone — a natural feature, generally stable and often invisible except against light. Colour bands are zones of different tone, valued when they add contrast and disliked when they look patchy.
These features are not flaws in the technical sense; they are character. Photograph the piece against light to see them before deciding.
Reading flaws honestly
The rule is simple: cosmetic features affect price and taste; structural ones affect safety. A bangle with a crack should be avoided or priced accordingly; a plaque with soft cotton is simply a different stone.
Buy from sellers who describe flaws rather than hide them. A piece with its character disclosed is worth more to you than a mystery piece at the same price.
This guide is general buying education. It is not an independent laboratory report or an appraisal. Confirm the facts of the individual piece before payment.
Frequently Asked Questions
What is cotton in jade?
Cotton is soft white cloudiness from looser fibre structure inside nephrite. It is cosmetic, not structural, and small amounts are normal in natural jade.
Is a crack in jade serious?
Yes. A crack is a structural break and a real risk, especially in a worn bangle. Ask the seller directly whether a piece has cracks, and get the answer in writing.
What is a water line in jade?
A water line is a pale translucent streak — a natural, generally stable feature that is often only visible against light. It is character rather than a structural flaw.
Should I avoid jade with flaws entirely?
No. Cotton, water lines and colour bands are normal in natural jade and simply affect price and taste. Only structural cracks deserve real caution.