?Chinese? Thumbring?

No, it doesn't look Chinese. What material is it made of?

If it is bronze, it is probably designed to be sewn onto a tube for a water pipe. There has been some suggestions that smaller ones were sewn into gloves to use as finger protection for archers.

However, the stitching would have been a weakness in any archery related use. I am guessing the size. If it is very large, I think that the water pipe is the explanation. I have seen jade and ivory ones from Indian in the Islamic style. They often are mistaken for thumb rings.

The biggest length is 43mm. The inner dia is 22mm and the material is bronce.

This would just fit on my thumb covering from below the distal joint to the tip of the proximal phalanx. The problem would be that the whole of the wrist would have to be rotated in order to bring the lip of the ring perpendicular to the string. This is an awkward and probably impossible angle to maintain with a bow of any strength.

In a Qing cylndrical ring, the back of the distal joint of the thumb can be pressed against the inside of the ring for purchase, but you cannot do that with this ring.

I think that this is a ring not meant for archery in any style we now use.

So could it be possible, that it is a thumbring. Has anybody examples for thumbrings?

See the technique section, there I sent pictures of a thumbring from Prof.Duvernay (Korean style).
;-) Uli

Actually,
I was suggesting that it is not a thumb ring.