Can anyone tell me how this rainbow cloud is formed?

https://lemmy.ca/post/55001912

Cloud iridescence! . Typical with thin high atmosphere clouds. When very small ice crystals or water droplets form the cloud they can diffract the light from the sun, causing an interference pattern to form. Not entirely dissimilar from an oil slick.
Cloud iridescence - Wikipedia

Thanks a bunch. Are they more common in hot countries? Never seen them in Canada.
Am Canadian. Have seen them. It’s more about altitude than lattitude.
Last night’s sky was especially amazing.
I see them in the Midwest quite regularly. If you’re outside enough, you see them.
What part of Canada? If west coast, probably the clouds are just typically too low and thick.
Northern Ontario
I’m in a hot country and I have only seen it twice in my life with about 20 years between the two times.