Exodus 28:10

six ¹  of their names on one stone, and the six remaining names on the second stone, according to the order of their birth. ² 

Ge 43:33; Ex 1:1-4

¹ tn This is in apposition to the direct object of the verb “engrave.” It further defines how the names were to be engraved – six on one and the other six on the other.

² tn Heb “according to their begettings” (the major word in the book of Genesis). What is meant is that the names would be listed in the order of their ages.