Cirrocumulus clouds are white, upper-level clouds that are a combination of cirrus and altocumulus clouds. These clouds appear in a wavelike or cirrcular pattern in the sky. These clouds are very thin and are often hard to see because of how high up cirrocumulus clouds are.
This type of cloud froms from shallow convection or orographic lift, which is when the clouds pass over mountains. Cirrocumlus clouds mainly consist of supercooled water droplets, which can produce iridescence. Now you know the science behind cirrocumulus clouds.