I repaired small chips in the varnish work using a varnish that was called "teak". It was a matter of putting a very small amount of varnish into the chip mark with a match head. When I was doing this the first time I noticed some spots that had been repaired this way before delivery. The varnish looks very dark in the tin. If the colour you use is not a good match you can removed the varnish with some turps on a cloth.