The /ʊə/ diphthong ranks eighteenth in frequency among the English vowels, which partly accounts for the shortness of this list.
39 of the 40 pairs are monosyllables. Spellings of /i/ include <ee>, <ea>, the letter names B, D, P and T, the musical note names mi and ti, Spellings of /ʊə/ are <oor>, <ure>, and <our>, together with the exceptional <ewe> and <ue> in crewel/cruel.
There might be some dispute over the <lure> spelling, as to whether there is palatalisation and whether that would render these pairs non-minimal. Note the partial homograph tours, plural of tour, and Tours, the French city with an anglicised vowel sound.
The mean density value is 1%. The 40 pairs make 31 semantic contrasts, giving a high loading of 78%.
alee allure B boor B's boors be boor bean bourne beans bournes bee boor bees boors been bourne creel crewel creels crewels creel cruel D dour lea lure leas lures lead lured lee lure lees lures me moor mead moored meed moored mi moor P poor pea poor pee poor she sure T tour T's tours T Tours tea tour tea Tours teas tours tease tours tee tour teed toured tees tours tee Tours ti tour ti Tours ye you'reGeographical: Outside English-speaking countries, most visitors are from Saudi Arabia, Hong Kong, Yemen, Japan, Venezuela, Vietnam, Jordan, Taiwan, RO Korea, Norway, Costa Rica, Ecuador, Poland, Malaysia and India. Average 17 visitors per month.
John Higgins, Shaftesbury, January 2011.