It is of a ruddy yellow colour.
Schmidt, indeed, considers that the star has changed colour of late years, and that whereas it was once very red it is now a yellow star.
This opinion does not seem well grounded, however.

The star _may_ have been more ruddy once than now, though no other observer has noticed such a peculiarity; but it is certainly not a pure yellow star at present (at any rate as seen in our latitude).

Owing probably to the difference of colour between Vega, Capella and Arcturus, photometricians have not been perfectly agreed as to the relative brilliancy of these objects.

Some consider Vega the most brilliant star in the northern heavens, while others assign the superiority to Capella.

The majority, however, consider Arcturus the leading northern brilliant, and in the whole heavens place three only before him, viz., Sirius, Canopus, and [alpha] Centauri.