Bartle, C.M.; Purcell, C.R. 1994 Measurement of the carat values of small rings containing gold . Lower Hutt: Institute of Geological & Nuclear Sciences Institute of Geological & Nuclear Sciences science report 94/41 4 p.
Abstract: Interest has been expressed by two commercial laboratories in a bulk non-invasive method for measurement of the carat value of small items of jewellery such as finger rings. (auths./KAL)