Can I mix clear finish with walnut finish?

[bob frost]

Can I mix clear finish with walnut finish in order to try to match an existing finish that I want to give a new coat?
I have a dining room table that is about 15 years old that has some finish worn off and some ( I think) are some water marks). I have tested a few spots with some clear Watco wiping varnish , but it needs to be a little darker.

[Scott Holmes]

You can... this is called a toner. Make sure you test to make sure the stain and varnish are compatible.

Generally toners are made with fast drying shellac or lacquer.

You may find it easier to apply glaze then varnish. Use a gel stain (glaze) to get the color you want, then varnish over it.