The /ɑ/ vowel is usually spelled <ar> but we also find <a> in ma, <aa> in baa and the letter name R. The /ɪə/ diphthong is spelled <eer>, <ier>, or <ear> in geared. It is questionable whether the word Korean uses this diphthong or is a three-syllable word.
This contrast is between a long vowel and a diphthong. The starting tongue positions are well separated and confusions are unlikely.
Interesting pairs include:
The density value is 1.54%. The pairs make 32 semantic contrasts, giving a loading of 51.6%.
baa beer baas beers baa bier baas biers baa'd beard char cheer cahrred cheered charring cheering chars cheers far fear farce fierce guard geared jar jeer jarred jeered jarring jeering jarringly jeeringly jars jeers Koran Korean Korans Koreans lard leered larn lien larns liens ma mere mas meres mar mere mars meres Mali merely pa peer pas peers pa pier pas piers par peer parred peered parring peering pars peers parr peer parrs peers parr pier parrs piers parlous peerless pass pierce passed pierced passes pierces passing piercing R ear R's ears rah rhea shah shear shahs shears shah sheer shard sheared spar spear sparred speared sparring spearing spars spears star steer starred steered starring steering stars steers tar tear tars tears vase veers
John Higgins, Shaftesbury, November 2009