"Dark sunspots" refer to areas on the surface of the sun that appear darker than the surrounding area. These spots are cooler than the rest of the sun, and they may indicate intense magnetic activity. Full definition
It was a little dark to use under my eyes, as I just recently got a tan, but I was able to use it on darker sunspots on my face, as well as a lighter coverage and it worked really well. (maybelline.com)
The spot - confining mechanism may help solve another puzzle, says solar theorist Douglas Gough of Cambridge University, United Kingdom: The sun is brighter overall when it has the most dark sunspots on its surface. (sciencemag.org)
The sun's magnetic activity waxes and wanes roughly every 11 years, generating more dark sunspots at the peak of the cycle and fewer at the trough. (sciencenews.org)