Eucalyptus deglupta or rainbow eucalyptus is a tall tree that is unique among Eucalyptus in that it's the only one to live in the rainforest and only one of four species found outside of Australia. It can be found in the Philippines, Indonesia, and Papua New Guinea, where it can soar up to 250 feet. While its height is impressive, it's really the tree's multi colour bark that makes it stand out. As the rainbow eucalyptus bark sheds at different times , it first reveals a bright green inner bark but over time, this ages into different colours, blue, purple, orange, and maroon.
For the UK really only grown as a novelty as it needs tropical temperatures and I don't believe large enough trees under cover would show off their bark display.