Town postmarks come and they go. They "come" by way of new discoveries. They "go" by way of delisting.
New discoveries still happen. The latest additions are Hana, Maui, type 282.013 (formerly listed as tentative) used in 1882, Kaupo, Maui,
type 255.01, used in 1899, and Honolulu type 236.11 (IV), used in 1864.
Readily accessible auction sites such as eBay influence people to clean drawers, closets
and attics of old paper accumulations so more discoveries can be expected. Verification of new postmarks is a
rigorous exercise.
When confirmed, new postmarks join the list of rarest postmarks. Attempts to count the number of strikes known among
the rarest postmarks have yielded the census found at Census of Rare Town Postmarks.
The census includes all of the postmarks for which thirty or fewer strikes are believed to exist. (See the full
rarity scale at Describing Postal Markings)
Delisting happens for one of two reasons. First is to correct a mis-identification. Another reason is to implement
a protocol change in how we catalogue postmarks. The change affected postmark type 235.01, a single lined circular
postmark. Many single lined circle marks (type 235.01) were made from a device
that began life as a double lined circle (type 253.01). Through wear or because
of ink building up and clogging the small space between the lines, the double lines became single. Holualoa type
253.01/235.01 is one of several cases where the strikes migrated to single circles. The following images show the
Holualoa postmarking device once created double circles. Later, the circles were single lined – the result of ink
clogging the space.