how could you tell it was from the Philly mint?聽

聽 I think you were really asking me this, as I'm the one who said that the coin was minted in Philadelphia. Generally speaking, coins that have no mint marks like this 1886 Morgan dollar were struck at the Philadelphia mint, which is the main U.S. mint. Before 1942 mint marks appear only on U.S. coins struck at branch mints. The exceptions would be for coins dated from 1965 to 1967, when the Denver and San Francisco mints also struck all coins without mint marks, for cents struck from time to time since 1975 at the San Francisco and West Point mint without mint marks, and for the non-collector versions of bullion coins made since 1986, which are struck at the West Point mint without mint marks. The Philadelphia mint used a "P" mint mark for the first time on wartime alloy five cent coins dated from 1942-45, on small dollar coins beginning in 1979, and on all circulating coins except for cents beginning in 1980. The "P" was also used on 2017 cents to commemorate the 225th anniversary of the establishment of the U.S. Mint in 1792.

聽 聽Morgan dollars were also made at the New Orleans and San Francisco mints in 1886. These are designated respectively as 1886-O and 1886-S. The "O" or "S" mintmark would be on the reverse below the small ribbon that unites the two sides of the wreath, which is above the space between the "D" and "O" of ''DOLLAR".聽

聽 The "Redbook" referred to in the topic I previously referenced contains basic information like this.聽 If you want to understand the basics of U.S. coins, you must obtain at a bare minimum a current or recent edition of it. It can be bought from its publisher at whitman.com.