It is a .....

... Tai Chi Ruler.

This one isn't ancient as it was hand-turned for me in Cottingham, East Yorkshire, not many years ago.

It is being held here as intended, in the palms of the hands. If you search on YouTube you will see it being used for health and vitality.

Thanks for offering your guess yesterday, I enjoyed all of them!

PS. The T-shirt was a gift from China but I've forgotten or never knew what it stands for. If anyone can help with a translation I'd be very pleased.