The following 3 Items are examples of covers which flew with the crew of Apollo 15 to the moon and then to the lunar surface with Cmd Scott & LMP Irwin aboard LM Falcon. They are of course the infamous 398 Sieger covers of two types and the personal Irwin Shamrock covers. Several different varieties exist which also flew on this mission but we'll concentrate on the three.
The Sieger covers consist of a 100 Type A
(no printer inscription on the cover upper left) and 298 Type B
(with a print inscription of three lines of text) ,this is important and will be broke down later. Additionally two of the covers where damaged/destroyed during the pre-flight cancellation process.
OK so the crew commander David Scott was pitched by H Walter Eiermann the idea of carrying at least 100 specialty prepared Onion Skin Type A
covers to the lunar surface during the mission.It was expressed by the crew who where in agreement to do this that there was to be no commercialization or advertisement of the covers and that no sale of these items would be carried out until after the Apollo program concluded.
Post flight a hand written notation was added in the upper left corner on the Type A
covers stating ( Landed at Hadley Moon,July 30 1971,Signed Dave Scott and Jim Irwin) and on the reverse is a typed and notarized inscription that reads ( This is to certify that this cover was onboard the Falcon at the Hadley _Alpine ,Moon, July-30- August 2,1971).
Now an additional 298 Onion Skin Type B
( printed inscription upper left of cover) where prepared to be distributed to each crew member( 100 each) for there own use. It is my belief that an additional 3 lines of text where added post flight which starts with the special character # and a small blank spot for a number to be hand inscribed followed by of 300 to the Lunar Surface in L.M. "Falcon".
All of these types of cover also bares all three crew members signatures at lower left.Also some of these have a none flown card inserted inside stating there authenticity some of which where also signed by crew members but not all.
And finally there are the 8 Irwin Shamrock rag cotton covers imprinted with a green shamrock,a small Apollo 15 emblem and a rendering of the lunar rover which was first used on this mission allowing the astronauts to venture further from the Lem during there excursions.Now 6 of these post flight where inscribed by Irwin on the front of the cover reading (Carried to the Moon) with his signature below and a circled number at lower left.
Two of the 8 covers where gifted to KSC workers due to there efforts in the design of this cover per Irwins request pre flight.On September 29 1971 the crew returned to KSC to thank the workers for the success of the mission and there support. This is when Irwin presented the covers to the two but the inscription differs reading,This envelope was flown to the moon on Apollo 15.
Upon receiving the covers from Irwin two 8 cent decade of achievement stamps where affixed to these covers and promptly canceled at the KSC post office. Note the Shamrock cover and Type A onion skin displayed here are non flown types canceled on the day of launch.
The Web site Space Flown Artifacts
does a great job completely breaking this down. This is just a general summary enjoy.