Pyrite

Spectrum Details

Modality

NIR

Category

mineral

Material Type

Sulfide

Sample ID

GDS483.c

Collection Locality

Armejun, Spain

Spectral Purity

1c2c3d4b # GDS483.c # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Composition / XRD

None # XRF, EPMA, ICP(Trace), WChem

Sample Description

Forms series with Cattierite (CoS2). Dimorphous with Marcasite. "SS-19. Pyrite. Rico, Colorado (35). Pyrite, FeS2, is the most common and widespread of sulphides. It occurs in igneous, metamorphic and sedimentary rocks, as well as in veins. In the visible, pyrite displays the reflectivity vs. particle size behavior that is peculiar to opaque minerals - ie. reflectivity decreases as particle size decreases. It is also interesting that decreased absorption in the red region of the visible results in a significant contrast in reflectivity from the red to the blue, despite the sample's overall low reflectivity. In the near-infrared, the spectral behavior of pyrite changes from that of an opaque material to that of a transparent one. This sample was ground from one of the original cubes of pyrite. Grain size fractions are indicated by the extension after the sample number: .a = 1000µm IMAGE_OF_SAMPLE: Not Available

XRD Analysis

Major pyrite with minor szomolnokite and minor rhomboclase. (Steve Sutley)

X Units

cm⁻¹

Y Units

Absorbance

Data Points

2,126