By default git blame is without color (none). But you have two nice configs for git blame:

git config --global blame.coloring highlightRecent

and

git config --global blame.coloring repeatedLines

highlightRecent

The Blame is displayed with different colors. Dependent on the old of the commit. By default:

blue,12 month ago,white,1 month ago,red

This you can change with the following config:

git config --global blame.coloring color.blame.highlightRecent

repeatedLines

All repeating lines that have the same commit ID, author and time are colored cyan. This makes it easier to see the related commits per line.

And yes, you can also change this color:

git config --global blame.coloring color.blame.repeatedLines