Do creams placed on the hands, face, or feet (such as Vaseline) prevent water from reaching [the skin] during wudu'?

These ointments, such as Vaseline, if they are solid and form a layer that prevents water from reaching the skin, must be removed before purification (ablution/ghusl). However, if they are not solid, they do not block the water, but one should rub their hand over the greased area when washing the limb so that the water does not slip off it.