Development of Genetic Models and Exploration Criteria for Gem and Pegmatite Deposits

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Gem deposits are fascinating because the geological conditions needed to produce them are exceptional. I study many types of gem deposits, but pegmatites are particularly interesting because they also produce strategic elements (such as lithium and tantalum). I also study beryl and its gem varietals (emerald and red gem beryl) and borosilicate minerals because they can tell us much about how pegmatites form. Over the past six years my students and I have investigated many gem occurrences in Canada. On Baffin Island we studied sapphire deposits and discovered that they formed by three sequential metamorphic reactions and that the best place to look for new occurrences is close to a thrust fault. Elsewhere in Nunavut (NU), we initiated research on the Anuri emerald occurrence. In British Columbia (BC) we studied a ruby and pink sapphire occurrence and learned that the gems formed at peak metamorphism from muscovite in silicate layers in marble. In the Northwest Territories (NWT) we confirmed that the Lened emerald occurrence is related to magmatic processes and that there is potential for the more valuable Colombian-type emerald deposits. Also in the NWT we have begun studying the origin of gem-tourmaline-bearing pegmatite dikes associated with the O'Grady batholith. In Utah we are studying the origin of red gem beryl; this inspired a comprehensive study of the crystal chemistry of beryl. A study of borosilicate minerals is also in progress. My long-term vision is to help develop a coloured gem industry in Canada; my research program advances this vision by determining how these deposits form and therefore how to make new discoveries. My short-term objectives are to: (1)Develop deposit models from the known occurrences. (2)Develop and test exploration criteria for each type of gem deposit. (3)Determine the origin of the water and the nature of the relationship between water molecules and sodium in beryl and to define the stability limits of beryl. (4)Use boron isotopes in borosilicate minerals to expand our understanding of Earth processes. Define new species and controls on the symmetry and stability of the sakhaite-harkerite series. Proof that a locality has a coloured gem resource would be transformative for communities. Advantages of coloured gem mining are that the industry can be developed on many scales, from the individual who collects rough to large-scale mining, and that it has less environmental impact than other mining. In addition, international recognition of such a resource in northern Canada would strengthen Canadian sovereignty. I will train a diverse group of 10+ highly qualified personnel. I will be conscious of using equitable and inclusive recruitment and mentoring practices through methods such as unconscious bias training and mentoring programs for underrepresented groups. My students learn valuable skills through both field and lab work and are expected to graduate having published at least one scientific paper.