Rainbow clouds were seen over Congleton this Christmas, with reports from across the UK made earlier this week.

One of the highest clouds in our atmosphere, these clouds are often referred to as "mother-of-pearl".

The phenomenon is rare, the clouds spotted in the UK because of the exceptional conditions needed to produce the rainbow effect.

These clouds form in cold conditions over polar regions and within the stratosphere, around 12-19 miles (19-31km) high, far above normal clouds.

This usually happens in altocumulus, cirrocumulus, lenticular and cirrus clouds. Iridescent clouds happen because of diffraction – a phenomenon that occurs when small water droplets or small ice crystals scatter the sun's light.

Some have dubbed the event a festive miracle, the clouds bringing a ray of light all the way from the arctic this festive season.