CJK Unified Ideographs Extension C

CJK Unified Ideographs Extension C is a Unicode block containing rare and historic CJK ideographs for Chinese, Japanese, Korean, and Vietnamese submitted to the Ideographic Research Group between 2002 and 2006, plus five "urgently needed" characters added in Unicode versions 14.0 and 15.0, some of which had previously been mistakenly unified with other characters.

The block has dozens of ideographic variation sequences registered in the Unicode Ideographic Variation Database (IVD). These sequences specify the desired glyph variant for a given Unicode character.

Note that the Katakana ligature 𪜈 (U+2A708) has been erroneously encoded in this block as a Han character.

History
The following Unicode-related documents record the purpose and process of defining specific characters in the CJK Unified Ideographs Extension C block: