It is common to find a layer of laquer on these silver and copper
vases. It is the yellowing of the laquer that often gives them their
patina look. I just use a laquer thinner to remove the laquer from
the vase. It takes some time for the thinner to soften the laquer,
but it does come off after a few applications. Be sure to use a very
soft cloth to prevent scratching the surface of the vase when you
remove the laquer.