Casting guide
The I Ching Three-Coin Method
Throw three coins six times and build the hexagram from the bottom line upward. Give one coin face a value of 2 and the other 3; each throw therefore totals 6, 7, 8, or 9.
Old Yin
Broken yin line that changes to yang.
Young Yang
Solid yang line that remains stable.
Young Yin
Broken yin line that remains stable.
Old Yang
Solid yang line that changes to yin.
Why changing lines matter
The first six-line figure is the primary hexagram. Any 6 or 9 is treated as moving: flipping those lines creates a transformed hexagram. Oracle Mirror shows both figures and the positions of all moving lines, while leaving detailed classical line-text study to dedicated translations and commentaries.
Coins are not the earliest attested method
The three-coin method became a convenient later technique and does not have the same outcome probabilities as the older yarrow-stalk procedure. Oracle Mirror uses coins because the method is transparent and easy to reproduce in a browser, while keeping that historical distinction visible.