Enigmatic Scale

The enigmatic scale was described by Giuseppe Verdi in the late 19th century — he included it in an Ave Maria composed for a Milanese music journal in 1889 that challenged composers to harmonize it. The scale is genuinely unusual: it starts with a half step, then two augmented seconds, a major second, and ends with two half steps. The resulting intervals make it difficult to harmonise conventionally, which was presumably Verdi's point.

Construction

C enigmatic scale:
C  D♭  E  F#  G#  A#  B  C

Formula: 1  ♭2  3  #4  #5  #6  7

Step pattern: H - A2 - A2 - W - W - H - H
(A2 = augmented second)

Two consecutive augmented seconds near the bottom of the scale are highly unusual — no common scale or mode has this pattern. The #4 and #5 are the whole tone scale's territory, the ♭2 is Phrygian territory, and the major 7th brings it back to a leading tone. It's an odd combination.

Ascending and Descending Forms

Like the melodic minor scale in classical theory, the enigmatic scale traditionally has different ascending and descending forms:

Ascending:  C D♭ E F# G# A# B C
Descending: C B B♭ A♭ G♭ E D♭ C

The descending form is much closer to natural minor — it drops most of the raised notes. For most improvisation purposes, only the ascending form is used.

Sound and Use

Genuinely strange and unsettling — the consecutive augmented seconds make it sound unresolved and chromatic in a way that doesn't fit any conventional harmonic framework. It's not "exotic" in a familiar flamenco or Middle Eastern way; it's more like a puzzle that resists categorisation.

Practical use is limited — it appears in avant-garde and contemporary classical composition, in music explicitly designed to evoke mystery or strangeness, and occasionally in extreme metal. For most musical contexts, more established exotic scales (double harmonic, Hungarian minor, Phrygian dominant) are more useful because they have established idiomatic applications. The enigmatic scale is an interesting study in how far you can push the seven-note diatonic framework before it breaks.