I have one that blooms like that, where the petals fade to a flat grey color when they age. I have not ID'd it yet though.

Springwood, we have several of these macros (NOID) and I adore them! Unfortunately, it's late in the season so the color is not as vibrant deep purple as it was last month.

Yes, these fade to a deep gray and pinkish color, very pretty!

Ah, yes the change of color! I read that in Japan there are many people who actually do not like hydrangeas because the bloom color is not stable and changes. Of course, last I looked at my roses, I had similar color changes with them too! Ha! I agree it would be nice to have a bloom that remains somewhat of the same color throughout the growing season, more than what we now see.