R rotunda

The r rotunda (ꝛ), "rounded r", is a historical calligraphic variant of the minuscule (lowercase) letter Latin r used in full script-like typefaces, especially blackletters.

Unlike other letter variants such as "long s" which originally were orthographically distinctive, r rotunda has always been a calligraphic variant, used when the letter r followed a letter with a rounded stroke towards the right side, such as o, b, p, h (and d in typefaces where this letter has no vertical stroke, as in ∂, ð). In this way, it is comparable to numerous other special types used for ligatures or conjoined letters in early modern typesetting.

This symbol came in several different shapes, all of which were of x-height. The shape of the letter used in blackletter scripts Textualis as well as Rotunda is reminiscent of "half an r", namely, the right side of the Roman capital "R"; it looks similar to an Arabic numeral "2".

Like minuscules in general, the origins of the letter are in cursive writing as it was common during the medieval period, ultimately derived from scribal practice during Late Antiquity. The r rotunda shape of cursive r resembling the numeral "2" is also found in a number of medieval scribal abbreviations containing r, e.g. in the signs for the Latin word-final syllables ram, —orum and —arum.

There are variant forms for the r rotunda glyph. Also found in Textura manuscripts is a very narrow second variant, in the form of one solid diamond atop another atop a vertical stroke. Another form found in German typefaces was a variant of that previous, with the part of an "s" that looks like an integral sign atop something rather like a "c". This one can be found used also as the second "r" of a pair and following "e". A fifth form, used in the eighteenth century in some French italic typefaces, was a derivative either of the Schrift form of the minuscule "r", or of similar typefaces used elsewhere. Its form was of a backwards "J" set just after the same shape rotated 180 degrees. They were separated by a space smaller than the stroke width between them, and the whole character was slanted as though it were cursive. As this typeface had the "d" that curved to the left, it was used after that character as well. By this time, though, the character was the same width as a regular "r", so it was maintained because it appeared to its users to have some elegance, or to remind them of prestigious old calligraphy.

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