ABSTRACT
Although it is easily the least common diatonic triad, iii nevertheless appears from time to time and you should be aware of it. Example 6.2 shows the scale degrees that are supported by the iii chord and partially explains why it is so rare. The scale degrees supportable by iii are already strongly associated with I, V, or both. Being that I and V are far more stable and common, it stands to reason that iii should be little used. Note also that iii, when it does appear, most commonly supports 7ˆ, as shown in the second measure of this example, and the other two voicings of iii are vanishingly rare.
