Fill the vase with water by simply removing the cork. The copper gets a beautiful patina over time.
Depending on the environment the colour changes naturally. You can polish the copper stem by using
a damp soft cloth and copper polish.
The glass should be handwashed separately in luke warm water and rinsed and dried carefully.
Do not wash in dishwasher. If any plaque appears on the glass pour a little citric acid or lemon juice and wash.
You can also remove plaque if you put a little rice and citric acid and shake the vase. Rinse with warm water.