Iridescent and Lenticular clouds

Shooting on September 2, 2017, the usual lenticular clouds and a rare rainbow cloud cumulus lenticular.

So-called rainbow clouds are a relatively rare phenomenon. These clouds can be painted in all possible colors of the spectrum, but more often this color is pastel.
Iridescent clouds are formed from tiny water droplets of practically the same size. Iridescent clouds appear when the Sun occupies a strictly defined position in the sky and is almost entirely hidden behind denser clouds. As a result of the coherent diffraction of sunlight on thin clouds, these clouds are colored in different colors, since the rays of light of different wavelengths deviate at different angles. It often happens that the rainbow clouds after a while fade. Iridescent clouds can be formed on the basis of high-cumulus, cirrus-cumulus clouds and lenticular clouds, and very rarely in cirrus clouds.