A mount is skin, hair, and an armature. Moths and dust work on it, and some animals you may not own. In the overview Security for collectors the same limit applies as for ivory and for the insect cases.

The limit

Before the purchase you ask whether the species and the papers allow the piece. This text does not say how anyone obtains mounts.

Storing what you lawfully have

Tight against moths, dry, not in full sun, not in the open hall where everyone walks into it. Separate an infestation at once. The papers in the document safe. A fallen mount often cannot be saved, so keep it standing firm and not by the door.