Engraved feathers are most commonly associated with certain 1878 Morgan silver dollars, including notably the 8 Tailfeather varieties. Here mint workers hand engraved "feathers" between the eagle's legs and lower wing to fill spaces left empty due to die and design issues. These engraved feathers are commonly used to distinguish the various 8 tailfeather reverse types. They are sometimes referred to as "engraved tailfeathers", although technically these feathers are somewhat hazily between the lower wing and upper tail of the eagle.
The arrows below point to the engraved feathers on the reverse of an 8 tailfeather Morgan:
Other examples of engraved feathers can be found in various forms on other 1878 Morgans, including other 1878-P and many 1878-S varieties.
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