That's perfectly normal- it's a small safety device that looks like a key of some sort. A pin on the rebound block pulls/pushes it up and down to prevent the pistol from being fired if it should be dropped just right. Howver, there is a raised portion on the rebound block and an oposite raised portion on the hammer that connect and pushes the hammer out of the forward rest position until the trigger is released. This also keeps the pistol from firing when dropped- I don't know why the key-looking thing was added.
Rednecks... Keeping the woods critter-free since March 2, 1836. (TX Independence Day)
I'm going to use the words "clip" and "Long Colt" every chance I get. It grinds my gears to see new members attacked when we all know dang good and well what's being refered to.