Raman spectra of solidified agarose and Cy 7.5-infused agarose samples

The zipped folder contains the .fit and .peaks files, obtained by means of Fityk Software, of the deconvolutions of Augelite Raman and ATR-IR spectra from RRUFF Database. The deconvolutions are obtained defining in Fityk software the q-Gaussian and q-BWF functions. The content of the folder is supplementary material of the paper "Augelite Raman and ATR-IR Fingerprints obtained with q-Gaussian and q-BWF deconvolutions made by means of Fityk Software", https://doi.org/10.5281/zenodo.15007191

This dataset is the collection of 3112 minerals, their chemical compositions, crystal structure, physical and optical properties. The properties that are included in this database are the Crystal structure, Mohs Hardness, Refractive Index, Optical axes, Optical Dispersion, Molar Volume, Molar, Mass, Specific Gravity, and Calculated Density.

Introduction

The term ‘dielectric’ is applied to a class of materials - usually solids - that are poor conductors of electricity. Dielectrics are of significant technological and industrial importance, being essential functional components of almost all electronic devices. For most of these applications, they are required to be mechanically tough and thermally robust. The defining physical attribute of a dielectric is electric polarizability which is the tendency for charges to be non-uniformly distributed across a chemical bond. Most dielectrics contain dipoles due to their ionic bonds or covalent bonds with strong ionic nature. At a macroscopic scale, this implies that an external electric field can interact with these charges and result in various optical and electric phenomena.

Optically, dielectrics can be transparent, opaque, or vitreous. They can also be isotropic, biaxial, or fully anisotropic. The luster of gem minerals such as emerald, sapphire, and ruby is due to their high refractive index which causes white light to be split into its components. The presence of two refractive indices in a material can result in an incident beam being split into two rays that interfere with each other. This common phenomenon is called Birefringence. These effects are made use of in many commercially important applications such as transparent conductive oxides, liquid crystal displays, medical diagnostics, stress sensing, light modulation, etc. As an example, transparent conducting oxides (TCO) are derived from dielectrics by doping oxides with impurity atoms. TCOs do not absorb light in the visible spectrum rendering them transparent and are also conductors of charge. The most important application of TCOs is as the top electrode of solar cells where they allow light to fall on a semiconducting layer while capturing the released hole/electron to generate current. Airplane windshields have a thin coating of a TCO material on them that is used to generate heat by passing a current. This is necessary to keep the glass defrosted allowing the pilot visibility to navigate. Other applications of TCOs is as substrates in electronics, flexible displays, high definition TVs, and the screens of mobile smart devices.

The figure for merit for optical phenomena is the refractive index, which is defined as the ratio of the speed of light in the medium to the speed of light in vavacuum.

Provenance of Data

The list of minerals with individual pages in Wikipedia is given at: https://en.wikipedia.org/wiki/List_of_minerals. The ‘get’ method of the requests library is used to retrieve this page and the content is parsed using BeautifulSoup – a python library specifically engineered for parsing html and lxml content. The URLs for all the minerals given in this page is extracted using their ‘href’ attribute and are stored in a dictionary, along with the mineral name. Each of the webpages has textual information on the mineral (origin, etymology, variety, history etc.), images (cleavages, and other data) as well as an ‘Infobox’ on the right that tabulates some common mineral properties such as category, formula, strunz classification, crystal structure, unit cell, Mohs hardness, color, cleavage, fracture, luster, diaphaneity, specific gravity, optical properties a and refractive index. The soup object for the page is retrieved and the ‘table’ element with class name ‘infobox’ is extracted. The specified row heading and row data are then read into a dictionary which is wrapped in a class object. A class method writes this data into a csv file while another method writes the text from the webpage into a text file.

The American Mineralogist Crystal Structure Database at http://rruff.geo.arizona.edu/AMS/amcsd.php has a list of over 4000 minerals with their cif files. The name and the URL of all these minerals are found at http://rruff.geo.arizona.edu/AMS. From here, each mineral name and the corresponding URL is extracted using the approach outlined above. Accessing each page, we find the crystallographic information of the mineral. The a,b,c edge lengths and alpha, beta, gamma - unit cell angles are given at the top followed by a list of all atoms and their x,y,z positions. The header is extracted and stored in a pandas dataframe while the atomic species and their positions are saved into a separate CSV file. This is repeated for all the 4000 minerals. Before inclusion into the machine learning stage of this study, each of these
cif files are read and parsed into a vector with each cel...

Raman spectroscopy analysis was performed on a microbialite sample from Laguna Pozo Bravo to assess mineralogical variations through both macro- and microscopic observations. Spectra were acquired using backscattering geometry with a LabRam HR Evolution Raman microspectrometer, set to a resolution of 0.4 cm−1 and equipped with a He-Ne laser line (633 nm) at INQUIMAE (UBA-CONICET), Buenos Aires, Argentina. Beam power and acquisition times were optimised for each sample to obtain informative spectra without causing sample alteration. Spectra were recorded using a 50× microscope objective (spatial resolution of approximately 1 μm), with an exposure time of 10-30 s and three accumulations. For band identification, we consulted the RRUFF database (https://rruff.info) and complemented this data with detailed mode assignments from Post, J. et al.

Precompiled and ready to go databases from the RRUFF, SLOPP/E, and WURM public databases fro Raman spectra. These datasets are already formatted for the RamanLab software.

Download them, and put them in the top level of the RamanLab directory.

Supplementary material for Brown (2024), PhD thesis - Chapter 6 - The metamorphic footprint of western Laurentia preserved in subducted rocks from southern Australia

Figure S1. Raman spectrum of kyanite armoured within c. 1240 Ma coarse-grained garnet in sample FMC-1b and band assignments. Shown for comparison is the Raman spectrum of kyanite (532 nm) from the RRUFF database (ID R050450).

Figure S2. Zircon probability density distribution plots for western North America and southern North America. Dates from the upper Belt-Purcell Basin (and correlative Marqueñas Formation) and the lower Belt-Purcell Basin (and correlative Yankee Joe, Defiance, Black Jack, Piedra Lumbre, and Piegan formations) are obtained from Ross and Villeneuve (2003), Stewart et al. (2010), Jones et al. (2011), Doe et al. (2012), Doe et al. (2013), and Daniel et al. (2013). Dates from the Unkar Group and correlatives are obtained from the compiled data set provided by Mulder et al. (2018). ε_Hf values for detrital zircon from the Franklin Metamorphic Complex, Rocky Cape Group, and the Clark Group superimposed on zircon ε_Hf values from the upper Belt-Purcell Basin (UBP), lower Belt-Purcell Basin (LBP), Laurentian basement rocks (LA), Transantarctic basement rocks (TAM), and Unkar Group rocks (UG). Summary of ε_Hf references: RCG (Mulder et al., 2015, 2018), CG (Mulder et al., 2018), BP (Stewart et al., 2010; Doe et al., 2013), LA (Bickford et al., 2008; Hull, 2013; Wooden et al., 2013), TAM (Goodge & Vervoort, 2006; Goodge et al., 2008; Veevers & Saeed, 2011), UG (Mulder et al., 2018 and references therein). Abbreviations: CHUR (chondritic uniform reservoir), DM (depleted mantle).

Table S1. LA–ICP–MS U–Pb isotope results for FMC-17 detrital zircon. U–Pb isotope data is provided for zircon standards GJ-1, Plesovice, and 91500. (bd) signifies below detection.

Table S2. LA (SS)–ICP–MS U–Pb isotope results for FMC-17 detrital zircon. U–Pb isotope data is provided for zircon standards 91500, GJ-1, Plesovice, OG1, and QGNG. (bd) signifies below detection.

Table S3. LA (SS)–ICP–MS Lu-Hf isotope results for FMC-17 detrital zircon. Lu-Hf isotope data is provided for zircon standards mudtank, 91500, GJ-1, Plesovice, OG1, and QGNG. U–Pb ages used to calculate time-integrated Hf ratios are from both LA–ICP–MS and LA (SS)–ICP–MS analysis. Where the locations of Lu–Hf analyses on zircon grains correspond to the locations of previous U–Pb analyses using LA–ICP–MS, Hf(i) and ε_Hf values are calculated using the U–Pb ages from LA–ICP–MS (red text; Table S1).

Table S4. Additional details for laser-ablation and ICP–MS instruments used in this study.

Table S5. LA–ICP–MS major element, REE and U–Pb isotope results for zircon in samples FMC-1b and FMC-2c. Elemental data is provided for zircon standards GJ, Plesovice, and 91500, and for synthetic glass standard NIST-610. Normalisation using chondrite values from Sun and McDonough (1989). Eu/Eu* calculation is provided below Table. For FMC-1b zircon analyses, bold green = concordant Cambrian, bold yellow = concordant early to middle Mesoproterozoic, and bold grey = concordant early Palaeoproterozoic to early Mesoproterozoic. (bd) signifies below detection. Pb is Pb(204).

Table S6. LA–ICP–MS major element and REE results for FMC-1b and FMC-2c porphyroblastic garnet. Elemental data is provided for synthetic glass standard NIST-612 and standard GSG-1G. Normalisation using chondrite values from Sun and McDonough (1989). Eu/Eu* calculation is provided below Table. (bd) signifies below detection.

Table S7. Representative EPMA results for solid solution minerals in samples FMC-1b and FMC-2c. Major element oxide compositions are given in wt%.

Table S8. Ti-in-quartz thermometry results. Ti (ppm) concentrations acquired from armoured quartz inclusions in Mesoproterozoic-aged garnet using EPMA. Temperatures calculated using the method of Osborne et al. (2022).

Table S9. REE partition coefficients calculated for the average composition of c. 1480–1235 Ma zircon (population 2) and the compositions of individual c. 1240 Ma garnet analyses from FMC-1b. Average garnet compositions for core, mantle, and rim are given. Normalisation using chondrite values from Sun and McDonough (1989).

Table S10. Compilation of geochronological, lithological, and thermobarometric data from rocks located in north-west Tasmania, central-west Tasmania, and the Belt-Purcell Basin.