I thought of this when I saw the thread on favorite white roses, and then saw pink roses among the photographs on the thread. The posters were correct, of course: white roses usually aren't pure white. Some are white in some weather conditions, pink in others. Most white roses have tints of other colors: the lovely 'Mme. Jules Bouche' is touched with buff and honey in its center; the buds of 'Mme. Plantier' are stained pink--perhaps it opens pure white--my "not-Bouquet Tout Fait" (I think it's 'Glenn Dale') is pale yellow in bud but opens white; 'Alberic Barbier' also starts pale yellow and ages to white, often retaining a touch of lemon or gold at its center.

Some white roses aren't white at all, but give an effect of white. 'Mme. Alfred Carriere' is actually a very pale pink; so is 'Sharifa Asma'. 'Mme. Zoetmans' reads white, but is actually palest buff and pink. The white Rugosas, if I remember correctly, are pure, true, icy white. I don't like the color. The musk rose is pure white as well, but milk white, possibly caused by some opacity in the pigment. 'Dupontii', thought to be an offspring of the musk rose, has the same milk white color, a beautiful hue.