IT DEPENDS. BEFORE 2005, THE CENTER WEIGHS .60/OUNCE. IN 2005 (I BELIEVE) THEY CHANGED SOME OR MOST
TO .50/OUNCE, AND AROUND 2008 SOME OR ALL WERE SILVER CLAD, SO THE WEIGHT MEANS NOTHING THEN. DATES MAY VARY, AS WELL AS INFORMATION FROM CASINO TO CASINO. BUT THAT SHOULD GIVE YOU A GOOD IDEA.