7 CFR § 51.1403 - Kernel color classification.
(a) The skin color of pecan kernels may be described in terms of the color classifications provided in this section. When the color of kernels in a lot generally conforms to the “light” or “light amber” classification, that color classification may be used to describe the lot in connection with the grade.
(1) “Light” means that the outer surface of the kernel is mostly golden color or lighter, with not more than 25 percent of the outer surface darker than golden, none of which is darker than light brown.
(2) “Light amber” means that more than 25 percent of the outer surface of the kernel is light brown, with not more than 25 percent of the outer surface darker than light brown, none of which is darker than medium brown.
(3) “Amber” means that more than 25 percent of the outer surface of the kernel is medium brown, with not more than 25 percent of the outer surface darker than medium brown, none of which is darker than dark brown (very dark-brown or blackish-brown discoloration).
(4) “Dark amber” means that more than 25 percent of the outer surface of the kernel is dark brown, with not more than 25 percent of the outer 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.