For what it's worth: standard notation practice in music theory classes (at least when I was there) for analysing the harmonic structure of a piece of music (what chords is Beethoven using in this string quartet?) made use of Roman numerals. A tidy way of indicating the difference between major and minor chords was to use upper-case for major chords, lower case for minor chords. For example,

I ii iii IV V vi vii* I.

*The diminished triad (vii) had a little superscript degree symbol following it. Added-note chords would have a number following them, for example,

I IV V7 I or i iv V7 i

Augmented chords were followed by a superscript "+"

Now that I've thoroughly confused the issue. . . .

Don Firth