... to medicine, accurate machine, accurate measure and inspection an Rods jewels are made of sapphire/ruby ,they are widely applied to ... environments.Main types:sapphire/ruby rods jewels,single round end rods jewels,double round end rods jewels, jewel rotor laterl pin,etc.Specification ... single crystal α-Al2O3, natural agate, spinel, ceramic, etc. sapphire rod jewels