Thompson Center has no official published serial number list, but I can usually tell a general age by the model and serial number. The model is in most cases engraved on the barrel, ie Cherokee, Seneca, Hawken, New Englander, Renegade etc. and the serial number is stamped on the barrel itself or on the breech plug. You can also contact Thompson Center directly and they may be able to help.
You will have to call TC to find out.
Black Powder.
To the best of my knowledge unless you are a convicted felon you can own a black powder gun.
Contact T/C customer service through their website.
Chinese
I imagine state laws vary on this but in Texas you do not have to call anybody to transfer a black powder gun.
no rockets run on black powder (gun powder)
who made the gun. how do you know it's a black powder gun ????
Spain
Charcoal and saltpeter (if you mean black powder)
Black powder, or a black powder substitute such as Pyrodex. Smokeless powder (modern gun powder) should not be used in a traditional muzzle loading firearm.
The term is a black POWDER gun- meaning it shoots back gunpowder, and not smokeless powder. Some were patented, some still are. Patent- not Patton.