Reverse of 78-79

Parallel arrow feather

Two of the primary Morgan dollar reverse types are called the Reverse of '78 (or "parallel arrow feather") and Reverse of '79 (or "slanted arrow feather").
The Reverse of '78 (or "parallel arrow feather") is seen below and was used on all 1878-S coins, all 1878-CC coins, and some 1878-P coins (called 7 tailfeather/TF Reverse of '78), some 1879-S coins, and some 1880-CC coins. VAMmers will often call this reverse the "B" type reverse, and often "parallel arrow feather" is abbreviated as PAF. Notice how the top arrow feather is parallel to the bottom arrow feather (coin shown is an 1880-CC VAM-4):

Slanted arrow feather

The Reverse of '79 (or "slanted arrow feather") is seen below and was used on all Morgan reverses except the Reverse of '78 coins listed previously, the 1878-P 8 tailfeather coins (a.k.a. type "A" reverse), and the 1921-P/D/S coins. VAMmers will often call the Reverse of '79 reverse the "C" type reverse, and often "slanted arrow feather" is abbreviated as SAF. Notice how the top arrow feather is slanted and not parallel to the bottom arrow feather (coin shown is an 1878-P VAM-220):

There are other more subtle die features that distinguish the Reverses of '78 and '79, but the top arrow feather is the best tool for a quick diagnostic.
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