Minting/Production Error (6)
Philately - Air Mail (16)
Philately - Censored Mail (9)
Philately - Earliest/Latest, First/Last & Proving dates or places (5)
Philately - Late Fee (1)
Philately - Military Post Offices or Military Administration (2)
Philately - Multiple Postal Authority/Period mail (1)
Philately - Postal Stationary (3)
Philately - Printed Matter mail (3)
Philately - significant cachets & postal markings (4)
Philately - Significant franks on covers (30)
Philately - Significant Rates/Periods (11)
Philately - Small Locales (3)
Philately - stamp design/overprint variations (3)
Philately - Surface Mail (contemporary) (3)
Philately - Taxed Mail (2)
Philately - uncatalogued/undocumented varieties (6)
Philately - Unusual Origin, Destination or Postal Link (3)
Philately - unusual postal procedures/fines/taxes (3)
Unique/Discovery Piece (1)