The discovery of new mineral deposits contributes to the sustainable mineral industrial development, which is essential to satisfy global resource demands. The exploration for new mineral resources is challenging in Canada since its vast lands are mostly covered by a thick layer of Quaternary sediments that obscure bedrock geology. In the course of the recent decades, indicator minerals recovered from till heavy mineral concentrates have been effectively used to prospect for a broad range of mineral deposits including diamond, gold, and base metals. However, these methods traditionally focus on (visual) investigation of the 0.25–2.0 mm grain-size fraction of unconsolidated sediments, whilst our observations emphasize on higher abundance, or sometimes unique occurrence of precious metal (Au, Ag, and platinum-group elements) minerals in the finer-grained fractions (<0.25 mm). This study aims to present the advantages of applying a mineral detection routine initially developed for gold grains counting and characterization, to platinum-group minerals in < 50 µm till heavy mineral concentrates. This technique, which uses an automated scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer, can provide quantitative mineralogical and semi-quantitative chemical data of heavy minerals of interest, simultaneously. This work presents the mineralogical and chemical characteristics, the grain size distribution, and the surface textures of 2664 discrete platinum-group mineral grains recovered from the processing of 5194 glacial sediment samples collected from different zones in the Canadian Shield (mostly Quebec and Ontario provinces). Fifty-eight different platinum-group mineral species have been identified to date, among which sperrylite (PtAs₂) is by far the most abundant (n = 1488; 55.86%). Textural and mineral-chemical data suggest that detrital platinum-group minerals in the studied samples have been derived, at least in part, from Au-rich ore systems.

中文翻译：

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耕作中的铂族矿物的探索：一种新的回收，计数，矿物鉴定和化学表征方法

新矿床的发现有助于可持续的矿产工业发展，这对于满足全球资源需求至关重要。在加拿大，新矿物资源的勘探具有挑战性，因为其广阔的土地大部分被厚厚的第四纪沉积物所覆盖，这些沉积物掩盖了基岩地质。在最近几十年的过程中，从重矿物精矿中回收的指示性矿物已被有效地用于勘探各种矿藏，包括钻石，金和贱金属。但是，传统上，这些方法侧重于（目视）调查未固结沉积物的0.25-2.0 mm粒度级分，而我们的观察则着重于更高的丰度，有时甚至是独特的贵金属（Au，Ag，和铂族元素）细颗粒（<0.25毫米）中的矿物。这项研究旨在展示将最初开发用于金粒计数和表征的矿物检测程序应用于<50 µm的铂族矿物直至重金属精矿的优势。该技术使用配备了能量分散光谱仪的自动扫描电子显微镜（SEM），可以同时提供有关重矿物的定量矿物学和半定量化学数据。这项工作介绍了矿物学和化学特性，晶粒尺寸分布，以及从加拿大盾构（主要是魁北克省和安大略省）不同地区收集的5194个冰川沉积物样品的处理过程中回收的2664个离散铂族矿物晶粒的表面纹理。迄今为止，已鉴定出58种不同的铂族矿物，其中锂闪石（PtAs₂）是迄今为止最多的（n = 1488; 55.86％）。结构和矿物化学数据表明，所研究样品中的碎屑铂族矿物至少部分源自富金矿石系统。