Can you identify this cloud?

Question

These clouds have shapes smaller to those of cirrocumulus however, they are distinguishable from them in that they are larger and usually have definite dark shading underneath and in the middle of each element. They don't produce halo phenomenon but the edges of the elements are often thin and translucent and exhibit irisations, which are formed only in this type of cloud. What is the name of this type of cloud?

Answer 1

I'd never heard the word "irisation" but the American Meteorological Society glossary says this about it

irisation—The color exhibited by iridescent clouds and at times along the borders of lenticular clouds.

So the answer is lenticular clouds.  The formal name for these clouds is altocumulus lenticularis.  I have seen them many times but have never seen the irisation associated with their edges. You learn something new every day.

Answer 2

Cumulonimbus.

Answer 3

cumulus cloud