7 CFR § 51.1434 - Color classifications.
(a) The skin color of pecan kernels is described in terms of the color classifications provided in this section. When specified to a lighter color classification, that color may be used to describe the lot in connection with the grade.
(1) Light means that the kernel is mostly golden color or lighter, with not more than 25 percent of the surface darker than golden, and none of the surface darker than light brown.
(2) Light amber means that the kernel has more than 25 percent of the surface light brown, but not more than 25 percent of surface darker than light brown, and none of the surface darker than medium brown.
(3) Amber means that the kernel has more than 25 percent of the surface medium brown, but not more than 25 percent of surface darker than medium brown, and none of the surface darker than dark brown (very dark brown or blackish-brown discoloration).
(4) Dark amber means that the kernel has more than 25 percent of the surface dark brown, but not more than 25 percent of surface darker than dark brown (very dark brown or blackish-brown discoloration).
(b) U.S. Department of Agriculture kernel color standards, PEC-MC-1, illustrate the color intensities implied by the terms “golden,” “light brown,” “medium brown,” and “dark brown” referred to in paragraph (a) of this section. The color standards are available at: https://www.ams.usda.gov/grades-standards.