Aetites

In the magico-medical tradition of Europe and the Near East, the aetites (singular in Latin) or aetite (anglicized) is a stone used to promote childbirth. It is also called an eagle-stone,aquiline, or aquilaeus. The stone is said to prevent spontaneous abortion and premature delivery, while shortening labor and parturition for a full-term birth.

From Theophrastus onwards, the belief is also recorded that the stone had the ability to "give birth" to other stones, based on the crystals found within. This fed into the belief that at least some minerals could be gendered into male and female forms.

The aetites is a type of hollow geode; inside, small loose pieces rattle when shaken. An official publication of the United States Bureau of Mines in 1920 defined an aetite as:

A nodule consisting of a hard shell of hydrated oxide of iron, within which the yellow oxide becomes progressively softer toward the center, which is sometimes quite empty.

The American Geological Institute defines the eaglestone as "a concretionary nodule of clay ironstone about the size of a walnut that the ancients believed an eagle takes to her nest to facilitate egg-laying."

According to Dioscorides (5.160), the aetite should be fastened to the left arm to protect the fetus; at the time of birth, it should be moved to the hip area to ease delivery. He also recommends them for the treatment of epilepsy, and says that when mixed with meat they will "betray a thief".Pliny describes four types of aetites in his Natural History and outlines their magico-medical use:

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