Hildegarde von Bingam's childbirth advice

Hildegarde von Bingham, like many of her contemporaries, felt that the natural world had a lot to offer, and this was applicable to the pains which accompanied childbirth. This was not considered witchcraft, as stones were a part of the natural world, given to us by God, and therefore to be used in the proper way to help us.

You'll notice that the use of the sard in this instance, was not magical in the least itself, but coupled with an invocation to God to help the suffering mother. 

Here are the mineral properties of sard, as listed on the gemrockauctions website:

    Mohs hardness: 6.5-7

    Color: Reddish-brown, brown

    Crystal structure: Trigonal

    Luster: Vitreous (glassy), greasy, waxy, or resinous

    Transparency: Semi-transparent to opaque

    Refractive index: 1.53-1.54

    Density: 2.56-2.68

    Cleavage: None

    Fracture: Conchoidal or granular

    Streak: White

    Luminescence: None

None of this seems particularly helpful for a birthing mother. The most helpful thing in the advice from Hildegarde was to massage the thighs.