Micro X-ray diffraction as a discrimination tool for diamond exploration, using the mineral structures of ilmenite and chromite

2017年，加拿大矿业的矿产产量为440亿美元，矿物加工资本投资为40亿美元；数亿美元用于研发，矿业为加拿大人创造了63.4万个就业机会(NRCAN 2018)。North Arrow Minerals Inc.总部设在不列颠哥伦比亚省温哥华，是一家充满活力的加拿大公司，在加拿大各地勘探钻石。常规勘探方法使用金伯利岩指示矿物(KIM)的化学分析来确定金伯利岩的存在及其钻石潜力。我们建议与North Arrow合作，使用Flemming提出的双矿物结构方法，测试作为一种新的勘探工具的微型X射线衍射(MicroXRD)的应用。我们认为，钛铁矿和铬铁矿群体的显微X射线衍射/晶胞细化将是一种强有力的新的金刚石勘查工具。如果一群钛铁矿颗粒具有c轴14.02(±.01)ä，则表明为金伯利岩起源。结合钛铁矿晶胞提供的阳性金伯利岩鉴定，a轴=8.32(±0.01)ä的铬铁矿颗粒群表明该金伯利岩是含钻石的。(然而，铬铁矿的晶胞参数本身并不是决定性的。)我们创新的双矿物结构方法将为North Arrow提供一种新的金伯利岩勘测(通过钛铁矿单元)和钻石潜力估计(通过铬铁矿单元)的方法，这将使North Arrow在钻石勘探领域获得竞争优势。这种方法有可能从North Arrow的勘探预算中节省数千美元，因为它减少了通过电子探针微分析(EPMA)处理整套KIM的必要性。一旦将这项技术应用到他们的勘探计划中，将简化作业，并可能在钻探之前评估资源的钻石潜力。新的勘探方法可能会带来新的钻石发现，这将为加拿大提供财富。在加拿大培训的高素质HQP将走在下一代钻石发现的前沿。

In 2017, the minerals industry in Canada saw $44 billion in mineral production as well as $4 billion in capital investments for mineral processing; Hundreds of millions of dollars was spent on research and development and the minerals industry has created 634,000 jobs for Canadians (NRCAN 2018). Headquartered in Vancouver, BC, North Arrow Minerals Inc. is a dynamic Canadian company exploring for diamonds across Canada. Conventional exploration methods employ chemical analysis of Kimberlite Indicator Minerals (KIMs) to determine the presence of kimberlites and their diamond potential. We propose to team up with North Arrow to test the application of micro X-ray diffraction (microXRD) as a new exploration tool, using Flemming's proposed two-mineral structural approach. We propose that microXRD/unit cell refinement of ilmenite and chromite populations in tandem will be a powerful new reconnaissance tool for diamond exploration. If a population of ilmenite grains have c-axis < 14.02 (±.01) Å, this indicates a kimberlitic origin. In combination with a positive kimberlite identification provided by the unit cell of ilmenite, a population of chromite grains with a-axis = 8.32 (±.01) Å indicates that the kimberlite is diamondiferous. (The chromite unit cell parameter by itself, however, is not definitive.) Our innovative two-mineral structural approach will provide North Arrow with a new method of kimberlite reconnaissance (via ilmenite unit cell) and estimation of diamond potential (via chromite unit cell), which will give them a competitive advantage in the field of diamond exploration. This method has the potential to save thousands of dollars from North Arrow's exploration budget as it reduces the necessity to process the complete suite of KIMs by Electron Probe Microanalysis (EPMA). This technique, once implemented into their exploration program, would streamline operations and may enable estimation of diamond potential of the resource prior to drilling. New exploration methods could lead to new diamond discoveries, which would provide wealth to Canada. High caliber HQP trained in Canada will be at the forefront of the next generation of diamond discoveries.********