Yes, there are glued combos.
This one looks a bit like slate, not Blue - but it may be just the photo or dirt. If it's purplish when you clean / lap it - then you are in luck :)
Not PITA to use at all (at least - not for me) - I'd cherish it! I'd also venture that the yellow may not be very hard, some vintage coticules are kind of soft
Cheers
Ivo