Also called: Well pattern · Jing zi wen · Jade well mark · Yujing wen · Hash mark · Well-character pattern

Where on the hand: Most auspiciously on the Mount of Jupiter under the index finger (the Xun palace); also read on the Saturn mount (Li palace) and the Apollo–Mercury zone (Kun palace).

What it looks like: Two vertical lines crossed by two horizontal lines, making the Chinese character 井 — a clean noughts-and-crosses grid with a clear square at its centre. Chinese practice insists on exactly this four-stroke figure; a mesh of many crossing lines is a different, unlucky formation.

One of the most sought-after wealth marks in Chinese palmistry. On the Jupiter mount it is read as great influence in one's field and large wealth arising from it; on the Saturn mount, powerful patrons and helpers; on the Apollo–Mercury side, birth into a prosperous family. The 'jade well' name carries the sense of a well that never runs dry.

Read with care: This is the same figure Western palmistry calls a grille and reads as scattered energy, obstruction or nervous depletion. The two traditions flatly contradict each other on it: Chinese sources treat a clean four-stroke 井 as one of the luckiest marks on the hand, Western sources treat crosshatching as one of the worst. The difference lies partly in the definition — Chinese practice requires a precise, sparse, four-stroke figure, while the Western grille is a dense irregular mesh. Softened: the valence reversal against the Western grille is real, but Chinese practice already has separate terms for meshes (方格紋/棋盤紋) and boxes (田字紋/口字紋), so 井字紋 is its own figure rather than 'the grille read differently'. That identification was this reference's synthesis.