Does it say J. Stevens AND Co or J. Stevens ARMS & TOOL Co or J. Stevens ARMS Co? The first would have been made from 1865 to 1886, the second from 1886 to 1915, and the third from 1920 to about 1945 (unlikely if it has damascus barrels). Value is $100 - $300 depending on condition, but only as a mantle decoration. Damascus or twist barrels were fine when they were produced, but were not intended for modern smokeless ammunition. Even if they were proofed for smokeless powder circa 1900, today's smokeless is not the same and after a century the barrels have probably deteriorated.
45-75
I'm not sure exactly what you're asking here. Generally a shotgun with Damascus barrels (those showing a spiral pattern on the outside, since they were made from spiralling layers of metal) will have been made for black powder only. In their time, fine Damascus barrels were considered a superior option, but caution should be exercised shooting such guns now, and definitely only black powder should be used. If in doubt, get the gun checked by a qualified gunsmith.
Crescent Firearms, J. Stevens Arms Co, Hopkins and Allen. The Utica name was a house-brand for Simmons Hardware, St Louis, 1875-1940.
Wall hanger.
Riverside guns were made by J. Stevens Arms Co, about 1900 +/- 15 years.
It would be most foolish to fire this gun. Laminated barrels are also called Damascan barrels and have been known to corrode and weaken where you can't see the damage. This was aggravated by the black powder shells in use at the time the gun was new. Modern smokeless powder has much higher pressures. The barrels can blow up. You are best to hang this gun on the wall and never use it again.
There are barrels outside the lighthouse and recycling center.
TRY THE FORUM ON GUNBROKERS.COM WEBSITE
My bet is that you are out of luck on this question. The bible for looking up info. on old shotguns is Bob Hinman's "The Golder Age of Shotgunning" and all he has to say about F. A. Loomis is "Hammer 12 guage, laminated barrels. No proof marks. nothing further known". My bible is Charles Carder's "Sides By Sides Of The World For Y2K", and it says Loomis was likely a dealer (maybe in Connecticut) for whom guns were made by Crescent Arms Co of New York. Much longer entry for Crescent. Guns were both laminated barrels and steel. Locks were both outside hammer, and hammerless. I have one, steel barrels, outside hammers, wish I knew what the numbers meant (mine is 13) and what in heck is I.X.L.?
American Gun Co was a house brand of H&D Folsom Sporting Goods in New York City and also sold through Sears Roebuck catalogs. Manufactured in Belgium and by Folsom's subsidiary company, Crescent Fire Arms in Norwich, CT, c. 1890-1930. With outside hammers, it was probably made before c. 1905. Look under the barrels for a proofmark of an oval with ELG and a star inside. If it is there, the gun was made in Belgium. If there is a crown over the oval, it was made after 1893.
I got this from Syrian writer Rana Kabbani (who wrote this in Vogue) : she wrote it was known as a fulla mutabbaqa, and it does not thrive when planted outside of Damascus. The flower "resembles a miniature cauliflower, but its prosaic shape belies its superlative scent : a heart-stopping mixture of gardenia and the deepest Arabian jasmine. Native to Damascus.
It's impossible to give a guaranteed answer without a lot more information, but I'll guess that you have either a single shot or double barrel 12 gauge and that it is complete and functional. If it has fluid steel barrels and back hammers or is hammerless it is probably still a useable firearm but if you have the urge to fire it have it checked by an experienced gunsmith first. If it has large side-mounted hammers it probably also has laminated steel barrels and should be placed over the mantle and cleaned occasionally. As either a useable shotgun or a wall decoration, a single shot will bring from $35 to $90 and a double from $100 to $250, depending on condition. Of course if it is so rusted worn and broken that it is useful only as a tomato stake or in factory-new condition, it will fall outside those ranges.