The /ʌ/ vowel is spelled with <u>, <o> in worry and <oo> in blood. The /eə/ vowel is spelled <ear>, <air>, <are> and <ar> in Pharaoh.
This is a contrast between a short vowel and a diphthong fairly well separated in the mouth. It does not seem to be a problem for many learners.
The density figure is 2.49%. The set makes 20 semantic contrasts for a loading of 83%.
blood blared borough bearer boroughs bearers bud bared bun bairn buns bairns buzz bares cud cared does dares dud dared flood flared furrow Pharaoh furrows Pharaohs fuzz fairs hurry hairy none Nairn nun Nairn scud scared scurry scary spud spared stud stared us airs worry wary worrier warier
John Higgins, Shaftesbury, December 2009