Large Coat Weight/Buttons: Made of lead, these are said to have served dual purpose, which I believe. Definite Civil War or before era. These are about 1.150" diameter. Found at Wilderness/South Mountain Area. Have two in this size.
These are exactly like the ones that were used in drapery hems when I was a kid. They are still made today, I believe.
Someone else researched 'em online: http://www.treasurenet.com/forums/what/333419-curtain-weights-hem-weights-what.html