Before I Toss Something That May Have Value To Someone Else.

While I will eventually post some inherited items which may be truly collectable, I want to confirm what a local shop told me today (by phone). Is it true that a post-marked stamp has little to no value to the collecting community? See the attached image.

My dad often kept mailed documents in their envelopes. Going through his stuff, I've come across several over the years. The attached image is a sample of 4 different envelopes (stacked).

Should I just throw them out? I've already scanned anything with a sentimental value and I don't want the keep them but I don't want to just throw them away if they have some sort of historical value to someone. What do you think?

75% of the time, this is correct. But it is not universally true. In some cases, a used stamp is more valuable that a fresh, never used example. Or, canceled examples are the only ones known (usually the case for early 19th century US stamps). And sometimes, it's actually the cancel itself that is the valuable thing. This may be the result of a post office only being open for a few days, or when a stamp gets withdrawn very quickly after its introduction, but someone was able to mail a letter with it. Or, if the cancel shows it was carried on a zeppelin, or by catapult or balloon mail.

There are collectors who go after nothing but cancels of a certain type or from a certain place. Others who collect mail ("covers") of a specific route, time, or event. Occasionally, the only known example of a stamp is found used, on a cover.

These appear to be Sc 657, 1058, and 1044, all from 1954, and aren't worth enough new or used to buy a pack of gum, sorry to say. Someone else will have to opine on the cancels themselves, though. Maybe something there, maybe not.

Interesting barrel cancels on the top and bottom envelopes. See http://goscf.com/t/42597

classic_paper and jogil, Thanks for the reply.
I'll save the envelopes for a bit. At least until I can take the actual collectables to someone to evaluate. I'm not expecting too much from the collection of stamps or coins. Some of the coins are ones made by the Franklin mint or similar types of manufactured collectables so I'm not sure how serious a collection it was. Of course I'm sure that even a manufactured collectable could someday for whatever reason, have some real value.

My concern would be throwing it all away knowing someone out there would say "You threw away that!". So if these things have any value to anyone, I'd rather they have it than the landfill.