Drinking mature champagne is truly a wondrous experience.

Dark golden yellow in the glass.
Doughy and lemon on the nose.
Very tiny bubbles and thin streams in the glass, but quite bubbly in the mouth.
Crisp, green apples, good acidity, creamy, rather balsamic vinegar-like, toasty, marzipan, dates and figs, very nutty (almonds and walnuts), rich Christmas cake-like fruit.
A rich and very complex wine that brightened up a Saturday night before Christmas.