Minimal Pair List Vowels 6 and 12, / ɒ / versus / ə / 3 pairs
This contrast is between a short vowel which cannot occur in an open syllable and the schwa which is always unstresed. In theory there could be a contrast in word initial position; if there was such a word as obbout it would contrast with about . In practice the only pairs that could be found in the dictionary were contrasts involving weak forms.
There is no point in calculating a density value.
on an on 'un oz as