Banjo C chord (Double C)C major on the 5-string banjo: 0 0 0 2, and 6 more shapes

Frets, string 4 to string 1: 0 0 0 2 (open position)

1. String 4 (C): open, C
2. String 3 (G): open, G
3. String 2 (C): open, C
4. String 1 (D): 2nd fret, index finger, E
5. String 5, the short g: open, G, in the chord

Sounds: C G C E  ·  C is C, E, G (1 · 3 · 5)

Found in: G major (IV), C major (I), G mixolydian (IV), D mixolydian (♭VII), C mixolydian (I), G dorian (IV)

The 5th string: the short g is the 5th of C, so let it ring.

Double C tuning: gCGCD, the short 5th string first, then strings 4 to 1.