Specimen data for Romanèchite

Tom Mortimer catalog number: 1637

Identification method: Gray streak, A first EDS analysis provided detector counts only:

EDS analysis counts: Ba (4.47) = 267; Mn (5.90) = 1499; Background 2/10 = 36/27

A second EDS analysis, this one with a plot: Romanechite EDS.jpg
A XRD analysis provided the plot below:

Cryptomelane XRD.jpg

Notes: This species was brought to my attention by Tom Minnich of West Swanzy, NH who kindly sent me several samples. These samples prompted me to re-examine a box of Mine Ledge specimens I had saved from past trips to this locale. I discovered that I had overlooked many samples of Romanèchite due to their similar appearance to the botryoidal, more common, goethite at this site. Initial identification of this specimen was Cryptomelane, the potassium, manganese, oxide, based on XRD analysis. Sebsequent EDS analysis showed dominant barium component and no potassium, hence Romanèchite identification.