Vowels 12 and 18, /ə/ versus /ɪə/     1 pair       [gluer.html]

The dictionary yielded 103 pairs, but all of them contrasted the schwa not with the /ɪə/ diphthong but with two vowels /ɪ/ and /ə/ forming two syllables. This distinction can cause mishearings, but they are not associated with any particular group of learners.

Meanwhile Peter Berry has suggested the pair gluer (machine for gluing) versus glue-ear (a medical condition), which is closer to true minimal pair, though there might also be a stress difference.

The density figure is irrelevant.

Alexandra Alexandria 
aural oriel
Beryl burial
beryls burials
boarder bawdier 
boner bonier
boozer boozier
bumper bumpier
Carron carrion
catcher catchier
cedar seedier
chatter chattier
choler collier
cholers colliers
chopper choppier
clamour clammier 
cocker cockier
corner cornier
corners corneas 
creeper creepier
curler curlier
dreamer dreamier
dresser dressier
dumper dumpier
duster dustier
falter faultier
fatter fattier
fisher fishier
freezers freesias 
gallon galleon 
gallons galleons 
genus genius 	   
gluer glue-ear
greaser greasier
groover groovier
harder hardier
header headier
jumper jumpier
laser lazier
lodgers loggias
lunar loonier 
lustre lustier 
manger mangier
meter meatier 
meters meteors 
mirrored myriad
mister mistier
mitre mightier 
moulder moldier 
mugger muggier
muster mustier
natter nattier
nipper nippier
oiler oilier
orals oriels
pallor pallier 
palmer palmier
Peter peatier
plumber plummier
plusher plushier
poker pokier
potter pottier
psalter saltier
racer racier
ratter rattier
reader reedier
redder readier 
rocker rockier
roomer roomier
rudder ruddier
runner runnier
salvers salvias
sapper sappier
saucer saucier
saver saviour
savers saviours
scatter scattier
serous serious 
shaker shakier
sirrah Syria 
sketcher sketchier
sleeper sleepier
smoker smokier
snorter snortier
sofa Sofia 
sponger spongier
spotter spottier
squeaker squeakier
steamer steamier
sticker stickier
straggler stragglier
stumper stumpier
sweater sweatier
taster tastier
tatter tattier
terror terrier 
terrors terriers 
twister twistier
venal venial
waiter weightier
waiver wavier
warier wearer
whisper wispier
wobbler wobblier

John Higgins, Shaftesbury, December 2009