庚 (Geng, Gēng, “Yang Metal (Six Yi)”) is one of the 9 Stems (三奇六儀) of Qi Men Dun Jia — one of the Six Yi (六儀), the ‘instrument’ stems that conceal the original 甲 leader stem during chart construction. The third Yi 庚 — yang metal, conceals 甲申, martial / cutting register; the most-watched of the Six Yi for conflict.
庚: classical reading and register
庚 (yang metal) is one of nine stems used in Qi Men Dun Jia chart construction. The Three Wonders (乙 / 丙 / 丁) are the most-favourable stems and represent classical 'wonder' registers (Sun, Moon, Star); the Six Yi (戊 / 己 / 庚 / 辛 / 壬 / 癸) are the 'instrument' stems that conceal the original Heavenly Stem 甲 during chart casting.
Classical attributes
Category: 六儀 (six yi)
Yi role:庚儀 (隱甲申) (Third Yi (hides 甲申))
Element: yang metal
Tier: challenging
Domain: The third Yi instrument; conceals 甲申; martial register, conflict, sharp force
Positive register
Military / security operations, decisive cutting of what is no longer useful, surgical interventions, contractual finality. The yang metal sharpness is favourable when the consultation specifically concerns ending or cutting.
Negative register
Unwarranted aggression, conflicts that escalate, contracts that end badly, the 'sword drawn at the wrong time' register. For most everyday consultations, 庚 is read as a warning sign — the most-watched of the Six Yi for potential conflict.
When to consult 庚
Read carefully — 庚 is the most martial of the Six Yi. Favourable for military / surgical / contractual-finality questions; warning for everyday matters.
Practical priorities
庚 as one of the Six Yi carries a more neutral register that depends substantially on the surrounding pattern.
Read the stem alongside the gate / star / spirit / palace sharing its location. Stems modulate; the surrounding components determine activation.
The third Yi 庚 — yang metal, conceals 甲申, martial / cutting register; the most-watched of the Six Yi for conflict. It is one of the Six Yi (六儀), the instrument stems that conceal the original 甲 leader stem during chart casting.
What's the difference between the Three Wonders and the Six Yi?
The Three Wonders (三奇: 乙 / 丙 / 丁) are the favourable stems classically associated with Sun / Moon / Star registers — wonders of celestial brilliance. The Six Yi (六儀: 戊 / 己 / 庚 / 辛 / 壬 / 癸) are the instrument stems used during chart casting; they conceal the six 甲 leader stems (甲子 / 甲戌 / 甲申 / 甲午 / 甲辰 / 甲寅) under their respective 戊 / 己 / 庚 / 辛 / 壬 / 癸 covers. The original 甲 is never directly visible in the chart — it operates through its concealing yi.
Should I look for 庚 specifically in my consultation?
Read carefully — 庚 is the most martial of the Six Yi. Favourable for military / surgical / contractual-finality questions; warning for everyday matters.
QI MEN DUN JIA FORECASTING
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Master Sean Chan’s Qi Men Dun Jia forecasting consultation reads the specific question you bring against the current dun period’s chart. The reading identifies which gates / stars / spirits are activating for your question, what classical patterns are present, and the favourable timing window for your action. Zero generic advice — every consultation is chart-specific.
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