How To Construct Postmark Classification Codes

A formal, rigid grammar does not exist for assembling the various codes into a postmark classification. However, an initial set of rules was established and enhanced over time with common convention. The following is an attempt to list the rules and conventions.
 
Separate sections are provided to describe construction of the different major Types and Codes:

Types 1 - 13

Type P

Type F

Code SL

Code SLO

Codes PPB, PPO, and PPK

Code RECD

Meter

Fake

 

Note that if an SL or SLO postmark occurs in combination with another postmark (usually Type 1 - 12), then the two postmarks are combined with a plus sign "+" with the SL or SLO postmark listed last. For example: 2tz + SLKb(n+), 9 + SLO "SOUTH CHINA/1936/PATROL", etc.
 
For the full description of the Locy System, numerous examples, and a listing of known cancel types for each ship, see the Catalog of United States Naval Postmarks published by the Universal Ship Cancellation Society.

 

---

Types 1 - 13

In general, the postmark classification code for Types 1 to 13 will have the following format:

 

<Postmark Type><lowercase variant codes> (<uppercase variant codes>,<distinguishing text>) comments

 

Use the following steps to construct the postmark classification. Note that the term current classification code means the code you have constructed so far. Codes are constructed from left to right.

 

1. Start with the <Postmark Type>. It must be one of the following values:

   1

   2

   3

   5

   6

   7

   8

   9

   10

   11

   12

   13

 

2. For Postmark Types 2, 7, 9, 10, 11, 12, and 13, add the -1 or -2 variant if appropriate. These codes immediately follow the Postmark Type with no intervening space (ie, 7-2, 11-1, etc.).

   -1	if "U.S. NAVY" is in the dial in addition to the ship's name.
   -2	if "FPO" and ZIP Code are in the dial in addition to the ship's name.

 

3. Add the uppercase L variant code if appropriate. If not applicable, continue on to the next step. If it is applicable, leave a blank space after the current classification code and then add the L in parentheses (ie, 2 (L), 11-2 (L), etc.). Traditionally, no further codes are added after an L since it was expected that an illustration of the postmark would be added to the USCS Postmark Catalog. However, comments may be added at the end of the postmark classification in order to identify characteristics that distinguish it from other L postmarks from the same ship / location.

 

4. If the ship has no name (ie, it is only identified via its hull designation and number), add the + variant code to the current classification code with no intervening space. For example: 2+, 9+, etc.

 

5. Add most of the lowercase letter variant codes in alphabetical order. Add them to the current classification code with no intervening spaces. For example: 6egipr, 2-2mt, 9+ef, etc. Do NOT include lowercase variant letter codes n, u, y, or z yet. They will be added in a later step. For now, only include the following lowercase letter codes if appropriate:

   a

   b

   c

   d

   e

   f

   g

   h

   i

   j

   k

   m

   o

   p

   q

   r

   s

   t

   v

   w

   x

 

6. Add the appropriate combination of the n and u lowercase letter variant codes, if applicable. Add them to the current classification code with no intervening spaces. For example: 6egipru, 2atnu, 2p(n+), 2et(n+u), 7qtn+u, etc. The following combinations are valid:

   n

   u

   n+

   n+u

   nu

   (n)

   (n+)

   (n+u)

   (n+)u

   (nu)

 

7. Add the y, z, #, *, (1), (2), (3), and -1 codes, in that order, as appropriate. Add them to the current classification code with no intervening spaces. For example: 6egipru-1, 6deip(1)-1, 9-1n+uy, 2az*, 2z#, etc. Note that for this case, the -1 variant indicates the presence of the numeral "1" inside the grid of a Type 6d or 6g postmark.

 

8. Now add the uppercase letter codes and distinguishing text as appropriate. All of the codes and text are placed within a section that is enclosed by a set of parenthesis. Most codes and text are separated from each other by commas, except where noted. The entire section is added to the current classification code after a single blank space. For example: 3s (AC-TBT), 9-1mt (D1,USN), 1y ("RECD"), 12-2(n+) (USS,FPO AP 96667-1232), 6 (AT SEA), etc. The codes and text are added in the following order:

    

   1. Add the A or B code if appropriate.

    

   2. Add the C or C+ code if appropriate. If A or B was added, add the C or C+ immediately after the A or B without an intervening space or comma. For example: 3 (AC), 2 (C+), etc.

    

   3. If the postmark is a Type 3 or Type 5, add the killer bar codes as appropriate. Valid codes for Type 3 are T, B, O, and X. Valid codes for Type 5 are O and X. There will always be three codes - one for the top, middle, and bottom killer bar, given in that order. If A, B, C, or C+ is present in the current classification code then add a dash before adding the mold line codes. For example: 3 (BC-TBT), 3 (BBB), 3 (A-OTO), 5bhks (XOO), 5bs (C-OOX), etc.

    

   4. Add the D1 or D2 code if appropriate. If uppercase letter codes are already present in the current classification code, then add a comma before adding the D1 or D2 code. For example: 2 (C,D2), 9-1 (D1), 3 (BC-TTT,D1), etc.

    

   5. Add the USN, USNS, and USS codes, in that order, if appropriate. If uppercase letter codes are already present in the current classification code, then add a comma before adding the USN, USNS, and USS codes. For example: 2-1 (USN), 9-1 (D1,USN,USS), 3 (AC-BBT,USS), etc.

    

   6. For postmarks with the -2 variant ("FPO" and ZIP Code in addition to the ship's name in the dial), add the FPO information exactly as it appears in the dial (include a forward slash "/" in the text if parts of the FPO code are separated). If uppercase letter codes are already present in the current classification code, then add a comma before adding the FPO information. For example: 9-2 (USS,FPO AP 94434-1323), 12-2 (FPO AE 95533), 12-2 (USS,FPO AP/96312-4432), etc.

    

   7. Add the AT SEA code for postmarks with "AT SEA" in the dial. If uppercase letter codes are already present in the current classification code, then add a comma before adding the AT SEA code. The code should match the uppercase / lowercase letters used in the dial. If the text in the dial uses all uppercase letters, then the code should use all uppercase letters. If the text in the dial uses mixed case, then the code should use mixed case. For example: 6p (AT SEA), 3s (AC-BTT,At Sea), etc.

    

   8. If the current classification code includes the lowercase y code, add the text that is associated with the y code. Add the text exactly as it appears in the dial (respect uppercase / lowercase lettering) and enclose it in double-quotes. If uppercase letter codes are already present in the current classification code, then add a comma before adding the quoted text. For example: 2ay ("RECD"), 11-1y (USN,"USPS"), 3sty ("Flagship/Fleet Base Force"), etc. Note that a forward slash ("/") indicates a break in the text - most likely by being on different lines or within different sections of the dial.

    

   9. If the postmark is a type 7 with lowercase variant code d (Type 7 postmark with wording or slogan in the killer), add the text that appears within the killer. Add the text exactly as it appears in the killer (respect uppercase / lowercase lettering) and enclose it in double-quotes. If uppercase letter codes are already present in the current classification code, then add a comma before adding the quoted text. For example: 7dit(nu) (USS,"POW/MIA"), 7-1dit(nu)y (USS,"STA,","FIRST DAY OF ISSUE"), etc. Note that a forward slash ("/") indicates a break in the text due to being on different lines.

 

9. Finally, add any comments related to the postmark. Things typically included in the comment section are year of first use (ie, 1955), range of years in use (1955-57), and anything else that might help uniquely identify the postmark but cannot be described by a standard code. Comments are added at the end of the postmark classification after a single blank space. For example: 9-1 (USN) 1987-93, 7-1t (USN) "CV" in dial instead of CVN

 

Examples:

2aty (USS,"DIRECTORY SERVICE")

5hks (C) period doesn't always show

8i

9-1(n+u) (B,USN,USS)

 

Return to Top of Page

 

---

Type P - Provisional Cancels

In general, the postmark classification code for Type P will have the following format:

 

P<lowercase variant codes> [<base Type> <description of alteration>] comments

 

1. The classification code must start with an uppercase P.

 

2. Add either the z or # variant codes if applicable. No other lowercase letter variant codes are known to occur. The variant code is added immediately after the P. For example: Pz, P#.

 

3. Leave a blank space and then add a section enclosed by square brackets. Within this section are two parts:

    

   1. In the first part, identify the original postmark Type from which this Provisional postmark was derived.

    

   2. In the second part, describe how the original postmark was altered.

 

4. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

P [2(n) with "A" removed] 1973-84

P [3t with "UNITED STATES FLEET" in dial and "USS PENN/FLAG" in killers] 1935

 

Return to Top of Page

 

---

Type F - Fancy Cancels

In general, the postmark classification code for Type F will have one of the following formats:

 

F<lowercase variant codes> (<killer bar codes>) comments
- or -
F<lowercase variant codes> [<Common Design number>] comments

 

1. The classification code must start with an uppercase F.

 

2. Add lowercase variant codes if applicable. Typical lowercase letter variant codes are a, b, v, x, z, and #. The variant code is added immediately after the F. For example: Fa, Faz, F#.

 

3. Leave a blank space and then add a section enclosed by parentheses. Within this section will be either one of the following (choose whichever is appropriate):

    

   1. If the postmark is supposed to have killer bars but some are missing, then add the O and X killer bar codes as appropriate. There will always be three codes - one for the top, middle, and bottom killer bar, given in that order. For example: Fb (OOX), etc.

    

   2. If this postmark matches one of the Common Designs, then add the CD number. For example: F [CD-1a], Fz [CD-Z2], etc.

 

4. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

F

Fvz

Fz no wording in bars

F [CD-5] Mar 29, 1975

 

Return to Top of Page

 

---

Code SL - Straight Line Postmarks

In general, the postmark classification code for Code SL will have the following format:

 

SL<K or P><line count><lowercase variant codes> (<uppercase variant codes>) (<measurements>) comments

 

1. The classification code must start with an uppercase SL.

 

2. Add either the K or P code, whichever is appropriate, immediately after the SL. For example: SLK, SLP, etc.

 

3. If the postmark has more than one line of text, add a numeral indicating how many lines of text are present. For example: SLK2, SLP3, etc. If no numeral is added, it is assumed that the postmark only had one line of text (ie, there should be no postmarks with an SLK1 classification). For SLP postmarks, the date stamp is not counted as one of the lines.

 

4. If the ship has no name (ie, it is only identified via its hull designation and number), add the + variant code to the current classification code with no intervening space. For example: SLK+, etc.

 

5. Add most of the lowercase letter variant codes in alphabetical order. Add them to the current classification code with no intervening spaces. For example: SLKbs, SLP2t, etc. Do NOT include lowercase variant letter code n yet. It will be added in a later step. For now, only include the following lowercase letter codes if appropriate:

   b

   f

   i

   l

   o

   s

   t

   y

 

6. Add the appropriate version of the n lowercase letter variant code, if applicable. Add it to the current classification code with no intervening spaces. For example: SLK(n), SLP3bn, etc. The following combinations are valid:

   n

   n+

   (n)

   (n+)

 

7. Add the appropriate uppercase letter codes in a section enclosed by parentheses. The codes are separated from each other by commas. The entire section is added to the current classification code after a single blank space. Only the C and USS codes are known to exist at this time. For example: SLKb(n) (USS), SLPt (C), etc.

 

8. Add a section enclosed by parentheses that contains the dimensions in millimeters, to the nearest whole millimeter, width by height. On multiple-line postmarks, the dimensions are those of the line with the ship's name. For example: SLK (32x3), SLP3b(n+) (USS) (45x5), etc.

 

9. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

SLPst(n) (55x3) 1940

SLKst(n) (USS) (53x3)

SLK3b(n) (68x5) 1949

 

Return to Top of Page

 

---

Code SLO - Slogan Postmarks

In general, the postmark classification code for Code SLO will have the following format:

 

SLO "<slogan text>" comments

 

1. The classification code must start with an uppercase SLO.

 

2. Then add the slogan text within double-quotes. Leave a single blank space between the SLO code and the quoted text. Respect uppercase / lowercase lettering (most of the time the text will be in all uppercase letters but sometimes it is mixed case). Include a forward slash "/" to indicate where text is split on different lines.

 

3. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

SLO "NON MAGNETIC ONLY/NO SUBSTITUTE"

SLO "Radio Controlled High Speed Development Unit/Light Target No. 1 (IX-35)"

 

Return to Top of Page

 

---

Code PPB, PPO, and PPR Postmarks

In general, the postmark classification code for Codes PPB, PPO, and PPR will have the following format:

 

<Postmark Code><lowercase variant codes> comments

 

1. The classification code must start with an uppercase PPB, PPO, or PPR - whichever is appropriate.

 

2. Add the z variant code if applicable. No other lowercase letter variant codes are known to occur. The variant code is added immediately after the postmark code. For example: PPBz.

 

3. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

PPBz

PPO

 

Return to Top of Page

 

---

Code RECD - "Received" Postmarks

In general, the postmark classification code for Code RECD will have the following format:

 

RECD (<Common Design number>) comments

 

1. The classification code must start with an uppercase RECD.

 

2. If this postmark matches one of the Common Designs, then leave a single blank space and add a section enclosed by parentheses that contains the CD number. For example: RECD (CD-R2), etc.

 

3. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

RECD (CD-R2)

RECD (CD-R3) used after POD

 

Return to Top of Page

 

---

Meter Postmarks

In general, the postmark classification code for Meters will have the following format:

 

Meter <Meter Type> (#<meter number>) <ZIP or FPO> <ZIP code / FPO text> comments

 

1. The classification code must start with Meter.

 

2. Add a single blank space and then add the Meter Code. For example: Meter PB1, Meter OFR2, etc.

 

3. Leave a blank space and then add a section enclosed by parenthesis. Within this section add a pound sign and then the meter number. For example: Meter OFR2 (#133994)

    

4. Add a single blank space followed by either the word ZIP or FPO, whichever is appropriate. After adding another single blank space add the full text of the ZIP or FPO Code (include a forward slash "/" in the text if parts of the FPO code are separated). For example: Meter OFR2 (#133994) ZIP 14493, Meter PB3 (#499493) FPO AP 14433, etc.

 

5. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

Meter OFR2 (#520240) ZIP 09544

Meter PB3 (#3300721) FPO 09544

Meter PB3 (#1459663) FPO AE/09578 ship's name omitted

 

Return to Top of Page

 

---

Fake Postmarks

In general, the classification for Fake postmarks will have the following format:

 

Fake (<Common Design number>) comments

 

1. The classification code must start with the word Fake.

 

2. If this postmark matches one of the Common Designs, then leave a single blank space and add a section enclosed by parentheses that contains the CD number. For example: Fake (CD-3), etc.

 

3. Finally, add any comments (see Step 9 in the Types 1 - 12 description above).

 

Examples:

Fake

Fake (CD-3)

Fake (CD-3b, "Eagle") Jan 2, 1942

 

Return to Top of Page

 

---

Copyright 2024 Naval Cover Museum