not rare
Examples
A. It’s not rare but it’s not common for an African American to have blue eyes.
The waterlogged soil forms a barrier for decomposing organisms and it is not rare to discover centuries-old wet mummies in the local graveyards.
And according to Caroline, my reaction to seeking help is not rare or unique.
Chengdu Taste has received several accolades in other markets, but here in Houston, where Sichuan cuisine is not rare and, more important, great Sichuan food is really just around the corner, it’s hard to say who truly reigns supreme.
Finally, it sometimes happens that the pronunciation of words might be changed because of their connection to Ancient Egyptian: in this case, it is not rare for writing to adopt a compromise in notation, the two readings being indicated jointly.
However, exceptions to this rule are not rare in the world's languages.