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Interpersonal violence is a rising issue in global society and new approaches are being sought to combat the problem. Within this context, expanding forensic techniques to better document violent crime scenes is critical for improving and acquiring legal evidence, such as proving or tracing contact between victims and suspects. This project aims to demonstrate the potential for forensic investigations in the context of interpersonal violence using a field-based reflective spectroscopy approach. For this, a common cosmetic, Wet‘N’Wild “Color Icon” blush in the shade “Pearlescent Pink”, was mineralogically characterized using transmission electron microscopy and powder X-ray diffraction and subsequently investigated via reflective spectroscopy on a variety of common substrates. Differing amounts of the cosmetic product, ranging from 0.001 g to 0.075 g, were applied to a variety of substrates using a simple push method to simulate forcible contact and material transfer. Substrates included a pine wood block; (calcareous) sand from Tulum, Mexico; Ottawa sand; tile; Pergo wood; linoleum; closet material; carpets; and fabrics. The reflective spectra of cosmetic–substrate combinations were measured via an ASD FieldSpec 4 Hi-Res spectroradiometer. The Wet‘N’Wild cosmetic was reliably detected on various substrates relevant to crime scenes. Minor amounts (as low as 0.02 mg/mm2) could be detected, and average limits of detection of 0.03 mg/mm2) were achieved; however, a calcareous sand (Tulum) had a high level of detection (>0.38 mg/mm2), suggesting that further investigation is needed for more complex sand substrates. The use of the ASD spectroradiometer as a forensic tool within the context of crime scene documentation shows promise. Future work should expand the characterization of cosmetic materials across a broad range of substrates and consider systematic studies of specific population groups. Furthermore, combining this approach with hyperspectral imaging at crime scenes is a promising future direction for crime scene documentation. This work therefore demonstrates a novel method for investigating cosmetics within the context of interpersonal violence and provides a foundation for future laboratory and field work using the ASD FieldSpec 4 and hyperspectral imaging systems. 

Plasma furnace processing has the potential to transform solar cell production. If informed decisions regarding silicon ore and mineral exploration can be made such that waste streams are also of high economic value, then production is ultimately more environmentally integrated. This study presents results from a spot check of the Kinnikinic Quartzite, ~4.5 km east of Arco, Butte County, Idaho (43.639091°, −113.243295°), for ore quality. The mineralogical and geochemical characteristics are explored within the context of a planned plasma furnace project at the sampled site and are compared to previous consulting reports. X-ray diffraction analysis detected only quartz, while scanning electron microscopy identified quartz grains, secondary quartz cement, trace amounts of potassium feldspar, minor iron oxides, and secondary illite. The bulk chemical characterization of 20 samples (including repeats) reports several wt. % variation in SiO2 from 96.47 to 99.66. Other notable chemical components include Al2O3, K2O, CaO, and Rb, all consistent with the presence of potassium feldspar (and illite). Gold concentrations vary from below detection (n = 12 out of 20) to a maximum concentration of 0.086 ppm. Total sum REE concentrations vary from 13 to 143 ppm. Conservatively and optimistically, assuming ideal extraction and recovery in plasma furnace operation, a resulting waste stream would have approximately 15.2 ppm (0.488 oz./metric ton) gold and 3400 ppm REE in the average waste. Gold (and REE extraction) may, however, be complicated by the presence of Fe and Cu if cyanide approaches were implemented. Gold concentrations are significantly lower than reported in previous work, warranting further characterization of this unit locally and regionally in order to characterize ore potential. This study works to demonstrate the possibility of evaluating other potential silicon ore units, such as the St. Peter Sandstone in Illinois and Missouri, for the co-production of materials in support of an emerging green economy.