Need Help Evaluating 2 Covers From The Early 1800's

I have two letters from 1827 and 1828 that I came across in a collection of family papers. Both were written at a time when the letter itself was folded to make its own "envelope". Both have post office cancellations. I assume that they would be properly classified as covers.

Are covers like this of interest to the stamp community? If they are and I wanted to sell them where would I offer them? Are there things I should be looking for in other similar letters I have that would make them of interest to a collector? The letters are mostly business letters and probably do not have any historical significance. A few between ship captains in the West Indies and merchants in Massachusetts are interesting to read, but they do not have cancellation stamps.

I believe they are called stampless folded letter sheets, and yes the are of interest to cover collectors.
Boston and New York cancels are common for these.
The ones between ship captains in the West Indies and merchants in Massachusetts are likely of more interest - when you say " but they do not have cancellation stamps" they should still have manuscript markings that indicate that ;postage was paid.

Small point of order: there is no "stamp community." There is only a broader "philately" (the study of postage stamps, stamped envelopes, postmarks, postcards, and other materials relating to postal delivery) community, in which we all participate to varying degrees in the aforementioned branches. The covers you have are part of an area called "prephilately" (concerned with postal systems prior to the introduction of postage stamps); many auctions and others sellers (retail or otherwise) have sections dedicated to the topic.

These would sell on ebay for $20-$50 at best. Very collectible, but selling them is not going to make you a fortune.

There are several reasons folks collect these treasures known as postal history items. Some for the postal markings, some for the history their contents document, and some for their personal or family connection to both. Like stamps, most are not going to fund you kids college education; but, there are sleepers out their that are quite valuable.

There are many on line resources available to help explain their franking and route of travel. And then some document the existence of very early small post offices.

Thank you for your replies to my post.This is a subject I know very little about.

I have many old letters and stamps that I don't want to keep, but which I don't want to throw away if they are interest to someone. I suspect that some of what I have might be of interest to a collector but I have no idea what.

There may not be interest in family letters from the late 1700's and early 1800's but I also have remnants of a relative's collection which at one time was notable.The New York Times described part of the collection in an auction announcement in 1932 as: "Of exceptional importance among the January sales...includes more than 600 lots on original envelopes...the largest single offering of this kind at auction in many years...heading the list of rarities is a fine copy of the rare Baltimore provisional, 5 cents, of 1845 on an envelope sent to Philadelphia"

"heading the list of rarities is a fine copy of the rare Baltimore provisional, 5 cents, of 1845 on an envelope sent to Philadelphia" - definitely was a very good item
"I also have remnants of a relative's collection which at one time was notable" - hard to say whether what is still left is of any significance or not.
"I have many old letters and stamps that I don't want to keep, but which I don't want to throw away if they are interest to someone. I suspect that some of what I have might be of interest to a collector but I have no idea what."
So we need more pics!

Unless there is something historical about the contents, or unless there are unusual markings or from (not to) famous people, stampless folded letters from the early 1800s tend to sell on ebay in the $3 to $10 range depending on several factors. East coast cities and large cities tend to sell on the lower end as they are plentiful with limited demand. Please provide photos of any particular covers you have and we can give you a good idea of whether they are common and inexpensive, or have good value, or have high value. You should also go on ebay and search on something like "stampless folded letter". IGNORE the starting bids as many sellers there try to get less knowledgeable buyers to start at a price that is well over full retail and in too many cases the sellers are either uneducated about actual values or in some cases are deliberately looking to trap unknowledgeable buyers into paying many times full retail. Instead, look at the sorting options down the left side of the page and click on "SOLD" items. Do this for at least several weeks and preferable for a few months and you will get a good idea of the value of your things. That will show you the actual prices collectors have really paid for these.