The catalogue value is $0.20 for either mint or used. Therefore, the market (retail) value is not much more than either face value if mint and a few pennies if used.
US Scott Number 1 issued in 1847. It has a Catalog value of $6,500 mint and $600 used.
That would be US Scott Number 2097 It has a minimal value of 20 cents used and $1.50 in mint condition.
The Scott catalog number for this stamp is 2137. The breadwagon stamp was not issued in 1866, it was issued about 1981. The item pictured was made in the 1880's. The stamp has a minimal value used and can be purchased for about a dollar mint.
{| |- | Scott Number 2111. These are the first class stamps issued when they weren't sure of the final value of the postal rate hike. They have a face value of 22 cents. They are still valid for postage within the US for 22 cents. |}
The Scott company has cataloged every stamp issued in the world. A Scott number of 760 would indicate that the stamp is for regular postage and is about the 760th stamp issued by that country. It would typically need a country with the number. If this is a US stamp it is a 5 cent vertical format commemorative of Old Faithful with a value of a few dollars.
That would be Scott number US 1906. It has a catalog value of 20 cents used and 35 cents mint.
{| |- | Scott Number J95. This was issued in 1959. You can purchase one of these for 20 cents used and mint from a dealer. This minimum value indicates that it has no real value. Consult a stamp catalog such as Scott's, for a description on how stamps are rated and graded. |}
Scott Number 1235 pictures Cordell Hull. This 5c stamp was issued in 1963. It has a minimal value used and can be purchased for 80 cents in mint condition.
That would be Scott Number US 3660. In mint condition is has a catalog value of $1.50 and the minimal 20 cent used.
It is important to know the catalog number and the quality of the stamp.
{| |- | This is Scott Number 1735. These are the first class stamps issued when the post office is not sure what new stamp value will be approved. They have a face value of 15 cents. They are still valid for postage within the US for 15 cents. |}
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