|Title||Automated indicator mineral analysis of fine-grained till associated with the sisson w-mo deposit, New Brunswick, Canada|
|Author||Lougheed, D H; Mcclenaghan, M B; Layton-Matthews, D; Leybourne, M I; Dobosz, A N|
|Source||Minerals vol. 11, issue 2, 103, 2021 p. 1-26, https://doi.org/10.3390/min11020103 Open Access|
|Alt Series||Natural Resources Canada, Contribution Series 20200681|
|Media||paper; on-line; digital|
|File format||pdf; html|
|Lat/Long WENS|| -67.1000 -66.9167 46.4167 46.2167|
|Subjects||mineralogy; Science and Technology; indicator elements; heavy minerals; heavy mineral analyses; tills; till samples; mineralogical analyses; mineral deposits; intrusions|
|Illustrations||location maps; diagrams; tables; graphs|
|Released||2021 01 21|
|Abstract||Exploration under thick glacial sediment cover is an important facet of modern mineral exploration in Canada and northern Europe. Till heavy mineral concentrate (HMC) indicator mineral methods are well
established in exploration for diamonds, gold, and base metals in glaciated terrain. Traditional methods rely on visual examination of >250 µm HMC material. This study applies mineral liberation analysis (MLA) to investigate the finer (<250 µm)
fraction of till HMC. Automated mineralogy (e.g., MLA) of finer material allows for the rapid collection of precise compositional and morphological data from a large number (10,000-100,000) of heavy mineral grains in a single sample. The Sisson W-Mo
deposit has a previously documented dispersal train containing the ore minerals scheelite, wolframite, and molybdenite, along with sulfide and other accessory minerals, and was used as a test site for this study. Wolframite is identified in till
samples up to 10 km down ice, whereas in previous work on the coarse fraction of till it was only identified directly overlying mineralization. Chalcopyrite and pyrite are found up to 10 km down ice, an increase over 2.5 and 5 km, respectively,
achieved in previous work on the coarse fraction of the same HMC. Galena, sphalerite, arsenopyrite, and pyrrhotite are also found up to 10 km down ice after only being identified immediately overlying mineralization using the >250 µm fraction of HMC.
Many of these sulfide grains are present only as inclusions in more chemically and robust minerals and would not be identified using optical methods. The extension of the wolframite dispersal train highlights the ability of MLA to identify minerals
that lack distinguishing physical characteristics to aid visual identification. |
|Summary||(Plain Language Summary, not published)|
This study focuses on improving mineral exploration techniques in regions covered by thick layers of glacial sediment, like parts of Canada and northern
Europe. Traditional methods involve examining larger mineral grains found in tills to search for valuable minerals like diamonds, gold, and base metals. In this research, the scientists used a more advanced method called mineral liberation analysis
(MLA) to study the smaller mineral grains, which hadn't been done much before.
By using MLA, they were able to quickly analyze thousands of smaller mineral grains in a single sample, providing detailed information about their composition and
shape. They tested this technique at the Sisson W-Mo deposit, a location known for its valuable minerals.
The key finding was that MLA could identify valuable minerals like wolframite even at a distance of up to 10 kilometers from the source,
which was not possible with traditional methods. Additionally, other minerals like chalcopyrite, pyrite, galena, sphalerite, arsenopyrite, and pyrrhotite were found farther from the source than before.
This research is essential for improving
mineral exploration in regions with thick glacial sediment cover, potentially opening up new areas for mining and resource extraction. It can save time and resources by pinpointing valuable mineral sources more accurately and efficiently.