Finger ring with rotatable centre part

摘要

The center part (1) of the ring (2) is carried on balls (2) to complete a self centering inclined ball bearing with the ring but without ball cage. The ring center part is in line with the outer ring end and thus not discernibly rotatable. METALLURGY - The balls can be of gold, Pt, corundum or synthetic sapphire or ruby as also the parts of the ring itself.