Jamieson, Fausset and Brown on Song of Solomon 5:11

11. head ... gold--the Godhead of Jesus Christ, as distinguished from His heel, that is, His manhood, which was "bruised" by Satan; both together being one Christ (1Co 11:3). Also His sovereignty, as Nebuchadnezzar, the supreme king was "the head of gold" (Da 2:32-38; Col 1:18), the highest creature, compared with Him, is brass, iron, and clay. "Preciousness" (Greek, 1Pe 2:7).

bushy--curled, token of Headship. In contrast with her flowing locks (So 4:1), the token of her subjection to Him (Psa 8:4-8; 1Co 11:3, 6-15). The Hebrew is (pendulous as) the branches of a palm, which, when in leaf, resemble waving plumes of feathers.

black--implying youth; no "gray hairs" (Psa 102:27; 110:3, 4; Ho 7:9). Jesus Christ was crucified in the prime of vigor and manliness. In heaven, on the other hand, His hair is "white," He being the Ancient of days (Da 7:9). These contrasts often concur in Him (So 5:10), "white and ruddy"; here the "raven" (So 5:12), the "dove," as both with Noah in the ark (Ge 8:11); emblems of judgment and mercy.