Uranus’ ring system was discovered in 1977, not with a direct observation, but rather the rings’ effect on the light of a distant star. Although the ring particles are known to at least partially consist of ice, unlike the rings of Saturn, Uranus’ ring also has rocky components which cause it to be very, very dark. The system of rings is seen to consist of a number of very distinct ringlets.
Carpe Caelum Planetary Astronomy