Hornblende Fe

Spectrum Details

Modality

FTIR

Category

mineral

Material Type

Inosilicate

Sample ID

HS115.3B

Collection Locality

Brewster, New York

Spectral Purity

1c2c3b4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

Composition / XRD

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

Sample Description

Forms series from Magnesiohornblende to Ferrohornblende. "S-1E. Amphibole, variety Hornblende. Brewster, N.Y., (115B). This is an impure sample, deep green in color. It displays the double band structure in the 0.6 to 1.1 µ region that is typical of the presence of both the ferric and ferrous ion. The presence of a light gray contaminant (muscovite) raises the reflectivity of the sample which is most obvious in the largest size range, and explains the anomalous (lighter?) reflectivity of that size fraction. The hydroxyl bands are not so strong as in tremolite and actinolite, which is typical of hornblende. The very weak bands in the visible near 0.5, 0.45, and 0.5 µ are due to both the ferrous and ferric ions." Hunt, G.R., J.W. Salisbury, 1970, Visible and near-infrared spectra of minerals and rocks: I. Silicate minerals. Modern Geology, v. 1, p. 283-300. Grain size fractions are indicated by the extension after the sample number: .3B = 74-250 µm IMAGE_OF_SAMPLE:

XRD Analysis

40 kV - 30 mA, 6.5-9.5 keV File: hnbld115.out, -.mdi References: Borg and Smith (1969) Found: Clinoamphibole, minor mica, trace chlorite Comment: Pattern matches that of tremolite more closely than hornblende. J.S. Huebner, J. Pickrell, T. Schaefer, written communication(USGS)

X Units

cm⁻¹

Y Units

Absorbance

Data Points

1,801