You might also consider Anthemis punctata ssp. cupaniana Emrys. It
matches your description in every way and seems to have been quite
widely planted over the past 20 or so years. I've used it as ground
cover in dry, poor soil where it forms broad mats of very pleasant
grey green foliage smothered with 5 - 7cm. wide flowers on long (15cm
+) stems in spring and early summer. In wet winters, the foliage
becomes more green, but soon 'greys up' with the return of spring
sunshine.

Very easy to prop BTW - simply take 10cm. stem tips and insert them
into sharply drained compost, gritty sand or perlite. Kept moist and
lightly shaded, they root in about 2 weeks and are ready for planting
out a week or so after that.