Hi Rick, many thanks for your interesting facts and information.Hi JNS. Welcome to the Forum.
Your gun is what is commonly known as an Albanian Tanchika musket. And typical of the style. (there are a couple different English spellings used). Probably from Central or Northern Albania sometime during the first half of the 19th Century. The lock is of the common Balkan style used on most of these Tanchikas. The lock is missing it's hammer and mainspring. Likely cannibalized for use on another Tanchika. Probably during the 20th Century for another collector's musket. The reason for the design of the unusual fish-tail butt stock has never really been confirmed and is still open to speculation. Unless there is a date on the gun, it's almost impossible to accurately date these muskets. As with other Ottoman period guns, their builders never left any written type documentation as compared to their European counterparts.
Interesting the gun still appears to have all of it's original barrel bands (often some or all missing). With prime lock parts missing, and some of the pearl decoration, my guess is that it would fetch maybe about $300.00USD (?)
Here is what the gun would look like if complete:
Rick
jns