The r rotunda (ꝛ), "rounded r," is an old letter variant found in full script-like typefaces, especially blackletters. Between the Middle Ages and today, many ways of writing alphabetical characters were lost. Besides a variety of ligatures, conjoined letters, scribal abbreviations, swash characters, and the "long s" with its own ligatures, one was the "r rotunda". Like many of the practices listed, this variant form of that letter was originally devised either to save space while writing on expensive parchment or for aesthetic reasons. It became popular among typesetters, providing a visual diversity of form and beauty, particularly in blackletter typefaces.
This "r"-shape was used at first only after the letter "o". It progressed to follow any letter that ended in a curved stroke, which provided the missing "half" of the "r". Hence, in blackletter, it may follow the letters "b", "o", "p", or "d". Often it was used after "d", for in many of those old typefaces the vertical stroke of that letter was curled to the left (as it still is in the Icelandic letter "ð"). It never began a word. This symbol came in several different shapes, all of which were of x-height.
Original form 
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 a bit like an Arabic numeral "2".
This character form also played a part in a common scribal abbreviation. The tail was extended to the right and a cross-bar was put through it, producing a figure very much like the ancient Greek symbol for the planet Jupiter "♃". This stood for the Latin syllable ram as well as the genitive plural terminations, —orum and —arum. This abbreviation character could follow any other character.
Other forms 
Also found in Textura manuscripts is a very narrow second variant, in the form of one solid diamond atop another atop a vertical stroke.
One form used in blackletter looked quite similar to the currency sign for the British pound "£" without the crossbars "𐆒". But it had no loop at the top and its understroke was quite short.
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".
Italic form 
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.
Demise of the r rotunda 
Usage of the letter form was never widespread except in blackletter scripts, so it fell out of use in English during the 16th century as roman scripts became predominant. Modern cursive scripts use a letter r that has a resemblance to the r rotunda.
The letter was proposed to be added to Unicode in 2005. As per Unicode 5.1 the encodings are U+A75A Ꝛ latin capital letter r rotunda (HTML:
Ꝛ) and U+A75B ꝛ latin small letter r rotunda (HTML:
Before, the Medieval Unicode Font Initiative (MUFI) had allocated it in the Private Use Area (PUA) of medievalist fonts at U+F20E and U+F22D. Since the characters are available in Unicode, MUFI recommends that the Unicode code points be used, not the PUA code points.
Some fonts treat the glyph as a mere stylistic variant of "r" and may make it available by smart font features, e.g. Open Type 'hist', 'hlig', 'calt', 'salt' or 'ss**'.
- Michael Everson, Odd Einar Haugen, António Emiliano, Susana Pedro, Florian Grammel, Peter Baker, Andreas Stötzner, Marcus Dohnicht, Diana Luft "Preliminary proposal to add medievalist characters to the UCS", 2005
- "Latin Extended-D", Unicode Standard
- http://www.mufi.info/specs/MUFI-CodeChart-3-0.pdf http://www.mufi.info/specs/MUFI-CodeChart-3-0.pdf MUFI character recommendation version 3.0 p.207 (2009)