A: US stamps that have cancellation marks (they have been sent through the mail) are usually sold in “kilo ware” (2.5 pound) packages.  The used stamps can be on or off paper.

For general information on stamp collecting and assessing stamp values we recommend visiting the following sites:

  1. The American Philatelic Society: www.stamps.org
  2. Zillions of Stamps- www.zillionsofstamps.com
  3. AskPhil- the non-commercial, all-reference site sponsored by the Collectors Club of Chicago- www.askphil.org
  4.  Linns Stamp News- www.linns.com
  5. United States Postal Service- www.usps.gov.