The wine is Rauenthaler Baiken Riesling Auslese 1971, von Simmern, A.P. Nr. 33045 007 72.
In general, 1971 is one of the best years for German riesling since WW II, and many of the better wines of auslese and higher grades are holding well. The 1971s often are not as concentrated and tropical as the 1976s. However they are noted for their exceptional complexity and balance. Of course, as in every country, some not-so-careful estates manage to make fairly ordinary wines in the best years. I have heard the 1976's compared with a large Rubens nude and the 1971s with a high fashion model - but a healthy one and not anorexic.
This wine is bright, medium gold and is holding very well. It is very complex with very ripe yellow peaches and other temperate stone fruit rather than the mangos and papaya of many of the 1976s. I suppose you can find traces of mango if you try hard enough. There is some old riesling character with hints of smoke and minerals. There is enough acidity. The sweetness is not excessive, but sufficient. There are hints of honey. The finish is long. The two word description is "outstanding balance".