Locality: Ham-Weeks Mine, Wakefield, NH
Specimen Size: 4.5 cm specimen with central zone of black columbite. Samarskite-(Y) is 1 to 2 mm thick resonous-brown zone on right edge of columbite, (yellow arrow).
Field Collected: Gene Bearss - 1979
Catalog No.: 1742
Notes: Samarskite-Y verified by EDS analysis.
A second analysis an XRF Analysis (pdf)) performed on a polished grain of the display specimen by Fred Davis also gave support to the Ham-Weeks Samarskite-(Y) identification.
Locality: Ham-Weeks Mine, Wakefield, NH
Specimen Size: 2.5 cm specimen with unknown cream-colored oxide.
Field Collected: Don Swenson
Catalog No.: 1486
Notes: This specimen is slightly radio-active. This specimen was previously in my display as Ishikawaite. However an October, 2011 EDS analysis and a Nov. 2, 2011 XRF Analysis (pdf) performed by Fred Davis showed this specimen to be samarskite.
A Raman spectroscopy examination of two sample points on this mineral grain reported:
Point 1: Fair match to yttropyrochlore, uranopyrochlore, ishikawaite.
Point 2: Poor match to ishikawaite; worse match to samarskite-(Y); no match to columbite-tantalite/tapiolite.
The Raman analyst noted that the Raman spectrometer gives poor, noisy, spectra for heavy metal oxides like samarskite, uraninite, and some columbite-tantalite series minerals.
Locality: N. Sugarloaf Mtn., Bethlehem, NH
Specimen Size: 3 cm specimen with black, sub-metalic samarskite-(Y) in feldspar.
Field Collected: Gene Bearss
Catalog No.: 2090
Notes: Polished grain EDS analyses (BC264 & BC279) indicated samarskite-(Y). There is an unlabeled Y peak between the Ta and Nb peaks. Fred Davis computed Ercit plots ( Ercit plot 1 , Ercit plot 2 ) from these analyses.
Locality: N. Sugarloaf Mtn. Bethlehem, NH
Specimen Size: 5.3 cm specimen with 1.3 cm jet black samarskite mineral at top.
Field Collected: Gene Bearss
Catalog No.: 2089
Notes: A polished grain EDS analysis BC275B, showed a Nb, Ta, Fe, Y, U, mineral. The tiny bit of Se is likely a miss-identification by the instrument element assignment software.
This specimen gives a moderate response on my scintillometer.
Fred Davis opined: "the general trend for quantities of elements [for this specimen] doesn't fit [samarskite] (Fe and Y+REE swap places, quantity-wise). Qualitatively, yes, the elements are present but including quantity takes the match process up a notch with a little more certainty. None of [these possible] species has that much iron. [summarizing]:
Yttrocolumbite Nb+Ta > Y+REE > U+Th > Fe
Petscheckite Nb+Ta > U+Th > Fe > Y+REE
Ishikawaite Nb+Ta > U+Th > Fe > Y+REE
Samarskite Nb+Ta > Y+REE > U+Th > Fe
[This] N. Sugarloaf Nb+Ta > Fe > U > Y "
Locality: Moat Mtn., Hale's Location, NH
Specimen Size: 1.2 mm high samarskite-(Y) cluster
Field Collected: Bob Janules
Catalog No.: A Bob Janules collection specimen
Notes: Bob supplied an EDS analysis for this specimen. The samarskite-Y is likely the dark brown mineral exposed on the lower broken surfaces.