Spalted wood is wood that has been infiltrated by "waves" of decay, with each wave leaving a uniquely outlined stain-zone line.

NPR: Excerpt: 'A Splintered History Of Wood'

They discovered that, by shifting the "phase" of light so that the peaks of one wave line up with the valleys of an adjacent wave, the two waves cancel each other out, creating "shadows" between waves that are smaller than the waves themselves(see chart).

FORBES: Trick of the Light

In addition, Ahluwalia also designed a new engagement ring for Royal Asscher called Legacy in which the signature Asscher cut diamond serves as the center stone of the platinum wave-like ring, with diamonds of different cuts detailing each side of the ring.

FORBES: Royal Asscher Honors its Heritage with Glittering New Jewelry Designs

They discovered that by shifting the "phase" of light so that the peaks of one wave line up with the valleys of an adjacent one, the two cancel each other, creating "shadows" between waves that are smaller than the waves themselves(see diagram, p. 141).

FORBES: Trick Of The Light