Q. David Bowers (edited and updated by Mike Sherman): In 1853 when the authorized weight of the half dollar was reduced from 206.25 grains to 192 grains, the change was noted on the coins by the addition of a small arrowhead to each side of the date and rays above the eagle on the reverse. Otherwise the Liberty Seated motif remained the same as used from 1839 onward. Just two varieties were produced: the 1853 Philadelphia issue of which 3,532,708 were made, and the 1853-O with a mintage of 1,328,000. Examples of the type are readily available in grades from Good through AU. Uncirculated coins are scarcer, while truly superb Uncirculated pieces (above MS-65) are rare.
-- Reprinted with permission from "United States Coins by Design Types - An Action Guide for the Collector and Investor" by Q. David Bowers