You should probably take this to a professional coin dealer for an accurate valuation. The value would depend on the condition of the coin, the perceived cause of the error (e.g., is the "4" missing because of a die error or because someone went at it with sandpaper and ground it off the coin), the extent of the error, and how "interesting" the coin looks. A collector of error coins would probably pay at least a few dollars, but whether or not it would be worth markedly more depends on the abovementioned qualities.
Try to pick it up with a magnet.
If the nucleus is missing an atom, it will try to steel an electron from another atom.
The model 1936 was stamped as such for only the first year of production (released in 1937 I believe), and was re-branded as the Model 36 in the years that followed, so if you show the stamp "Model 1936", you are holding an original. This rifle is approx. 72 years old.
Modern English 1p coins are made of copper-plated steel. So yes, there is a tiny amount of copper.
twice as much
Filled die errors are very common and have little value if any.
Assuming you have a penny dated after 1982, it's actually made out of zinc -- it's just missing its outer copper layer. It has a retail value of a couple of dollars. If it's dated 1943, you have a standard "wartime" cent struck (btw, not "stamped") in steel to conserve copper for the war effort. Unless the coin is in like-new condition, it'll be worth 50¢ to $1.
Stevens 12ga. /mod dhead naught
100 USD or so.
The 1944 steel penny is worth between $75,000 and $110,000. This steel penny was minted by mistake and there were not a lot of them around.
A 1943 steel penny with no mintmark can be worth $.35 - $1.50
This is a very common error caused by a filled die and adds nothing the value of the coin.
The sketch above shows a component which is stamped out of sheet steel The square in the center is discarded These components are stamped out of a continuous steel coil with a width of 8.50 cms.
The missing 4 is likely due to a foreign substance in the die when the coin was struck -- not very rare. Collectors for this type of thing generally will only pay a dollar or less for it.
A 1943 steel penny is worth just that 1cent.
The copper of the penny will rub off the file
Stamped steel.