Ferguson: ^The /yoor/ sound is spelled -ure :
pure cure immature impure manure mature obscure secure.^
The /yoor/ sound can indeed be spelt , but also 'your',
and in 'nature' it does not spell the /yoor/ sound.
The main sound of the spelling is /cher/ (picture, future, adventure), but this can also be spelt (pitcher, butcher, thatcher).
So it's all a bit confusing for parents and children.
But back to -ure.
53 common words end in -ure. They include 31 with -ture, 30 of which end with /-cher/ (puncture, vulture...except 'mature').
Of the remaining 22,
11 end with a /yoor/ sound:
assure
cure
endure
insure
lure
manure
obscure
procure
pure
secure
sure
but 11 don't:
conjure
exposure
failure
figure
fissure
injure
measure
pleasure
pressure
procedure
treasure.
I have no idea how this is tackled in phonics lessons
or if this information can be of help to u, but those are the facts.
Masha Bell