These are classic circle studs in a small 4/5mm size made in 925 sterling silver with abalone shell. These exact same studs can be purchased in white shell or turquoise. Nickel and Lead Free, Non Allergic. 925 Sterling Silver Small 5mm sized studs 4mm stone/shell Oxidised finished. Matching turquoise or white shell available Dimensions: Length=5mm, Width=5mm