Zevachim 74 - Counting One at a Time
The following ruling was reported in the name of Rav: if a ring of an idol became intermingled with a hundred permitted rings, and afterwards one of these rings fell into the Mediterranean sea, they all become permitted, because we say that the ring that fell was the forbidden one.
What is the background of this ruling? The ring that was used for idol worship is forbidden for all use. Thus all 101 rings should be forbidden. However, by the Torah law, the forbidden ring should be nullified in simple majority. It is the Sages who removed this nullification. And it is the same Sages who reinstated the nullification in the case when one ring accidentally fell into the sea and is no longer available.
The ruling of Rav is completely at odds with our previous ruling that one forbidden sacrifice is not nullified even in ten thousand permitted sacrifices . Since the sacrifices are consigned to die, we should just wait till the first one dies, then say that this one that died was the prohibited one, and bring the rest! The answer: Rav's "ring" opinion follows only Rabbi Eliezer, but the majority of Sages do not agree to it.
Art: Rembrandt Van Rijn - A Young Woman Trying on Earings