This coin was on board the SS Republic when it sank in 1865 and spent decades underwater.
Because of this there is the shipwreck effect as noted by NGC.
SHIPWRECK EFFECT — Portions of the coin exhibit heavy to severe disturbance from saltwater exposure, with metal loss affecting the design. While accurate identification and attribution may be possible, it is no longer possible to draw conclusive determinations about the coin’s surface prior to saltwater exposure.