Perfectly clear to me, and likely clear to an audience with numismatic experience. Otherwise, you might consider identifying obverse, reverse and flan key with explanatory descriptions “obverse (anvil) die” and “reverse (punch) die” and “flan (coin blank)” pointing to the colored drawings of each.
Liv Mariah Yarrow 
Perfectly clear to me, and likely clear to an audience with numismatic experience. Otherwise, you might consider identifying obverse, reverse and flan key with explanatory descriptions “obverse (anvil) die” and “reverse (punch) die” and “flan (coin blank)” pointing to the colored drawings of each.