Seashell of Just-Intonation Triads

Each plotted point corresponds to a triad whose frequency ratio is l:m:n. A point (l,m,n) in lmn space is mapped to a point (x,y,z) in xyz space by x = m - l, y = n - m, and z = 2l - n. This point is then mapped to spherical coordinates (r, theta, phi), and the current plot is obtained by doubling theta and quadrupling phi.
The Z' axis corresponds to the size of the interval between the root and the highest note of the triad. Hue corresponds to the size of the interval between the root and the second note. The lightness of the color corresponds to the complexity of the chord as measured by Benedetti height (Tenny norm).