• ► Unidentified subjects by country‎ (135 C)

*

• ► Stamps to be categorised by subject‎ (10 C, 126 F)

A

• ► Unidentified art‎ (10 C, 114 F)

B

• ► Unidentified brands‎ (6 C, 3 F)
• ► Brick walls in unidentified bond‎ (16 F)

C

• ► Media needing chemical classification‎ (105 F)
• ► Unidentified Christian motifs‎ (1 C)
• ► Unidentified clouds‎ (75 F)
• ► Unidentified computers‎ (36 F)

D

• ► Unidentified diagrams‎ (6 C, 1887 F)
• ► Unidentified diseases and disorders of plants‎ (1 C, 49 F)

E

• ► Unidentified electronic devices‎ (7 C, 1 F)
• ► Unidentified events‎ (4 C, 15 F)

F

• ► Unidentified food‎ (18 C, 289 F)

I

• ► Unidentified inscriptions‎ (3 C, 8 F)

L

• ► Unidentified language‎ (4 F)
• ► Unidentified letters‎ (151 C, 64 F)
• ► Unidentified locations‎ (58 C, 817 F)

M

• ► Unidentified maps‎ (2 C, 6295 F)
• ► Unidentified mascots‎ (1 C)
• ► Unidentified mathematics‎ (6 C, 15 F)

O

• ► Unidentified objects‎ (38 C, 399 F)
• ► Unidentified organisms‎ (12 C, 90 F)

P

• ► Unidentified people‎ (26 C, 3 P, 2228 F)

S

• ► Unidentified subjects related to sports‎ (2 C)
• ► Unidentified structures‎ (8 C, 11 F)
• ► Unidentified symbols‎ (4 C, 81 F)

V

• ► Unidentified vacuum tubes‎ (empty)