It is probably the abbreviated manufacturer name Sumthing Special in Canada. I have a ring with the same letters.
A Buffalo Nickel stamped on a penny is worth $800.00. A Jefferson Nickel stamped on a ZN penny is worth $70.00. A Jefferson Nickel stamped on a CU penny is worth $60.00.
From what I understand some jewelers stamped in the ring size!
Slide the Top Lever to the right to open the chamber. Turn the shotgun upside down. Look at the end of the barrel between the receiver and barrel. Get a flashlight and you'll see a series of numbers stamped in the bottom of the barrel.
Most likely the pattern number
thomas jackson of london england
This may be an identifier of the setting stamped there by the manufacturer.
its stamped on the bottom
describe the type of shotgun and recheck the serial number
probably a manufacturer stamp
A "J" stamped on jewelry could mean that the manufacturer was Jardinay. Jardinay is a very popular jewelry company located in New York, New York.
Model designation
This shotgun is in the neighborhood of 100 years old. There is fairly extensive information online available on this shotgun.
$250-$350
Hopkins & Allen
Marks stamped on a ring may tell you the manufacturer as well as the composition and metal quality.
The 395 means how much pure silver is in the coin. It was stamped on by the manufacturer when the coin was made and it was possible to measure the amount.