The picture below shows a larger front and back view of this 1975 Paul Revere Charlestown To Concord Bicentennial CoinMedallion or Pendant. This coinmedallion appears to be made of pewter. It features a recessed image of Paul Revere on a charging horse. On the back is a bit about this Historic ride. It is marked on the front as follows:
1775 - 1975 PAUL REVERE CHARLESTOWN TO CONCORD
The medal or necklace pendant measures 1-1/4'' wide. It appears to be in good condition with some old spotting as pictured.