US 1/2 Dollar engraved S John’s Sunday School Lowell Mass. John Coggleshall Easter 1871
An unusual prize medal.
30.7mm milled edge silver.
10.07g both sides smoothed.
So this is the same size as the US Liberty seated half dollar but over 3g. light due to the smoothing.
I have not been able to trace John H Coggleshall so this needs further research.