[audor]

I am trying to find out everything I can about this: year manufactured, civilian/police/military (branch), type of round, and any other information you may have. It was a gift from my Grandfather, a gift to him from his uncle and something I plan to keep for a long time. I'd also appreciate any advice on preserving it, removing corrosion, and can it still be fired?

Markings:

Top of Barrel:
COLT'S PT F.A. MFG CO HARTFORD CT U.S.A.
PATENTED AUG.5.1884 NOV.6.88. MAR.5.95.

Side of Barrel:
COLT D.A. 38

Trigger guard:
Star with "I" in the middle

Chamber release lever:
Star with "I" in the middle
With the numbers 1689 below the star (I assume serial #)

Inside of arm holding the chamber (only visible with chamber open):
Star with "I" in the middle and 1689

Body underneath the arm (only visible with chamber open):
1689

COLT molded in grip

There are no other marking.