Research project: Gemstone origins along Australian and Asian Pacific margins
- Start date:
- Australian Museum Research Grant. Purdue Univ., Indiana, USA, London Uni.UK CODES, Univ. Tasmania, FEGI, Russia, UNSW SFRG’ AINSE Grants, Cluff Pacific Resources PL, De Beers, SA
Eastern Australia hosts a palette of gem deposits, which are mined in several areas. Among them are prolific sapphires, rubies, zircons, diamonds and spinels distributed in placer deposits. These gemstones originated from deep sources sampled by basaltic eruptions before dispersion and concentration into drainages. Detailed studies of the minerals yield clues to their parentage and conditions of their formation. They involve gemmology, mineralogy, geochemistry and geochronology and utilise a range of analytical techniques. More recently, these include Raman laser and laser ablation micro-analytical methods.
The results to date now form an extensive body of publications in international and Australia journals, books, popular articles and media programs. Several papers from this project were recently published in 2008 in a special Issue of Ore Geology Reviews.
The Australian studies provided some breakthroughs in defining the affinities of these gem materials. The studies have expanded into other areas with similar deposits along the Pacific margins from South-East Asia to eastern Russia, Colombia, South America and New Zealand, attracting further collaborators from Australian and overseas laboratories.
Present activities include preparation of a synthesis of East Australian gem corundum deposits for publication, a forensic identification of sapphires from an unknown New South Wales locality in a Japanese institution, a write-up of Zircon Zip as a major analysis of zircons from the Pacific margins, the completion of a study of South Island New Zealand zircons, and a survey in progress on ruby deposits in the Mogok, Myanmar region. Studies on the unique diamonds from the New England area, New South Wales continue, and aspects were presented at the 2008 International Kimberlite Conferences.