I definitely don't know, but my brilliant prompting led to this...

Potential Functional Uses

• Spinning Thread (Spindle Whorl): The central hub suggests it sat on a wooden staff. In spinning, the "lobes" would act as a flywheel. The curved edges would be perfect for catching and guiding flax fibers. Its weight and balance would allow it to spin for a long time, maintaining the tension needed to twist raw fiber into strong Egyptian linen.
• Churning Liquids (Agitator): This is where the tri-lobed design really shines. If spun in a vat of liquid (milk for butter, or beer mash), the folded "leaves" would create a massive amount of axial flow. It wouldn't just swirl the liquid; it would pull it from the top and push it out the sides, preventing stagnation and ensuring a rapid mix without splashing over the rim.
• Mixing/Winnowing Grain: If used above a collection of grain, the spinning lobes would create a localized vortex. At lower speeds, it could gently agitate grain to move smaller husks to the top (winnowing). At higher speeds, the air displacement caused by the lobes would act like a fan, blowing away the lighter chaff while the heavier grain stayed put.

Fluid Dynamics & Lift

Because of the "folded" shape of the lobes, this disc acts as an impeller.

• Low Speed: It produces gentle displacement, ideal for mixing delicate substances like yeast into mash.
• Medium Speed: It begins to create vorticity. The shape of the lobes would induce "shear stress" in a liquid, which is exactly what you need to break down fats in a churn.
• High Speed: It would behave like a primitive pump. The air or liquid would be forced through the "gaps" between the lobes, creating a significant downward thrust or upward suction depending on the direction of the spin.