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Thin section images of drill core and hand samples from the South Kawishiwi Intrusion, Duluth Complex, Minnesota

January 19, 2022

This dataset includes photographic images of thin sections created from hand samples and drill core sourced from the South Kawishiwi Intrusion, Duluth Complex, Minnesota, along with two shapefiles representing the locations of the samples and drill hole collars. The samples were collected and core was drilled in order to define copper-nickel-platinum-group element resources associated with the South Kawishiwi Intrusion in the Duluth Complex. The images of the entire thin section, both in plane- and cross-polarized light, were taken using a high-resolution digital camera on a macro stand. The data is organized into five zip files, containing three zip files with images sourced from drill core, one zip file with images sourced from hand samples and one zip file containing shapefiles. The zip files containing image data are organized into a folder containing the 'RAW' unprocessed .CR2 images and associated .xmp metadata files, and a folder containing processed .jpg images. Folders with "DH" in the folder name contain images taken from drill core samples. The folders with "hand_samples" in the file name contain images taken from the hand samples. The file name of each photograph correlates to the sample ID or name and depth (in feet) of the drill hole from which the thin section was sourced, and whether the photograph represents a plane-polarized (ppl) or cross-polarized (xpl) light image. For example, the "MEX-142W2-3486.2_xpl.jpg" file is a cross-polarized image of the thin section sourced from drill hole MEX-142W2 at a depth of 3486.2 feet. Multiple images from the same sample are identified with "(2)" in the file name. The .jpg and .CR2 images have Section 508 compliant metadata as per USGS section 508 compliancy officer guidelines. The .xmp files are included with the 'RAW' .CR2 files because the original .CR2 metadata cannot be altered. In order to add descriptive information to the metadata, the .xmp files must be included. The edited image metadata for the .jpg files can be viewed using software such as Adobe Photoshop, Adobe Elements, or windows file explorer. The raw .CR2 images edited metadata can be viewed in Adobe Photoshop and Adobe Elements, but is not viewable using windows file explorer. For the .CR2 images, only the original metadata, created when the photograph was taken, can be be viewed using windows file explorer.