(57) A item of jewellery includes a support element (92) provided with inner and outer zones, and first and second support surfaces which face one another and taper from the inner to the outer zones, wherein said taper provides a bisector (126) extending along the axis of taper, there being provided on each of said support surfaces first and second spaced recesses or protrusions, said support element (92) having a resilience; said item of jewellery also including a collet (70) for holding a stone or other item, said collet (70) including first and second collet surfaces complementary to the first and second support surfaces, said collet surfaces having a taper substantially corresponding to the taper of the support surfaces, each of said collet surfaces including first and second spaced protrusions or recesses designed to cooperate and fit together with associated recesses or protrusions of the support surfaces, said collet (70) being fittable to said support whereby each of said protrusions includes a surface extending substantially transverse to said bisector.