Leave it as is . It took a long time to get in the condition it is in. Be kind. Actually it is now only worth a nickel ,if spent. As a couriosity it is priceless. Also there is little chance a date can be brought up without totally destroying the coin.
The coin went into the ground originally in poor shape, very worn, acid in the ground then took it's tole. There is a sayin : to turn a VALUABLE COIN into a worthhless ,(TO COLLECTORS) Coin: "CLEAN IT"
If you want a BUFFALO (INDIAN HEAD) coin in good or better condition, COIN SHOPS sell them for as little as $1.00 and up. Most old coins we find while metal detecting are not in the best of condition. Due mainly to the type of soil they have been in . Silver coins and Gold coins ,are the exception, and usually
(unless damaged in recovery) come out of the ground in the same condition as when they went into the ground. Be Advised,, DO NOT CLEAN ,scrape,buff, polish, or otherwise alter the surface of a coin( soap and water and tooth brush, OK.) before you determine the coins
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rigin,age. condition,metal type,Etc.
YOU MAY have a valuable coin, and dont know it. Coin collecting is an interesting hobby that fits right in with metal detecting for coins and other treasure. As in the treasure hunting hobby , research is necessary to fully enjoy the hobby of Coln Collecting.
FYI Tom SR. "Capguntom"