Code of Federal Regulations Title 7. Agriculture § 7.51.2106 U.S. Extra No. 1

(a) For dissimilar varieties. 5 percent, including not more than one-fifth of this amount, or 1 percent, for bitter almonds mixed with sweet almonds;

(b) For doubles. 5 percent;

(c) For kernels damaged by chipping and/or scratching. 5 percent;

(d) For foreign material. One-twentieth of 1 percent (0.05 percent). No part of this percentage shall be allowed for glass and metal;

(e) For particles and dust. One-tenth of 1 percent (0.10 percent);  and,

(f) For other defects. 4 percent, including not more than one-fourth of this amount, or 1 percent, for split or broken kernels, and including not more than three-eighths of the former amount, or 1 1/2 percent, for seriously damaged kernels.