This is the first Cinderella stamp in my collection. Many thanks to my friend Corinne Pegler for sending me this sheet.
What is a Cinderella Stamp? - Definition from Wikipedia - "Virtually anything resembling a postage stamp, but not issued for postal purposes by a government postal administration..." The term also excludes imprinted stamps on postal stationery. Cinderella stamps are not normally listed in the main stamp collecting catalogs. If they are, it is usually in a separate appendix within the publication, and so they are sometimes called back of the book stamps.
This sheet with four stamps shows the tug Lyttelton at Lyttelton harbor, the tug at sea, the tug in Akaroa Harbor, and the tug passing Akaroa lighthouse. This was issued by the Tug Lyttelton Preservation Society in 1990, and all proceeds from the sale of these stamps go towards helping to maintain tug Lyttelton.