Koppa (letter) - Typography

Typography

Modern typography of the numeral Koppa has most often employed some version of the Z-shaped character. It may appear in several variants: as a simple geometrical lightning-bolt shape ; with the top part curved rightward, evoking to some degree the original uncial form ; in a characteristic shape with a shorter top arm slightly curved to the left, resembling a Hebrew letter Lamedh ; or with the same lamedh shape turned upside down . Other variants common in older print include shapes based on the open uncial form (, ). Some of these shapes may be indistinguishable from realizations of the other Greek numeral, Stigma, in other fonts. Koppa has also sometimes been replaced by a lowercase Latin "q", a mirrored uppercase "P", or a "5" turned upside down.

As with the numeral usage of stigma (digamma) and Sampi, modern typographical practice normally does not observe a contrast between uppercase and lowercase forms for numeric koppa.

The Unicode character encoding standard originally (since version 1.1 of 1993) had only a single codepoint for Koppa (U+03DE "Greek letter koppa") which was marked as uppercase and could be used either for an epigraphic or a numeral glyph, depending on font design.

An extra lowercase codepoint was introduced in version 3.0 (1999), as U+03DF "Greek small letter koppa".

In addition, a second pair of codepoints specifically for the original closed epigraphical shape (U+03D8/U+03D9 "Greek Letter Archaic Koppa" and "Greek Small Letter Archaic Koppa", Ϙϙ) was introduced in version 3.2 (2002). This left the older two code points (U+03DE/U+03DF, Ϟϟ) to cover primarily the numeral glyphs.

As of 2010, coverage of these codepoints in common computer fonts is therefore still inconsistent: while the most commonly used version of the numeral glyph will be located at the lowercase code point U+03DF in recent fonts, older fonts may either have no character at all or a version of the closed epigraphic form at that position.

Conversely, older fonts may have the normal numeral glyph at the uppercase codepoint U+03DE, while this position may be filled with any of several less common glyphs in newer ones. Since there had never been a consistent typographic tradition for a specifically uppercase numeral koppa, the typographer Y, Haralambous proposed two new variants for it, and, noting that he himself found them not "entirely satisfactory".

Nevertheless, a serifed version similar to his koppa was adopted as the reference glyph for the Unicode code charts, along with a lowercase form with heavy curved arms and pointed angles . Some current Unicode fonts have adopted these new shapes, while many font designers have opted for some combination of the more traditional glyphs, including the uncial and the lamedh-shaped ones.