“Orange-yellow iowaite crystals. FOV 7.0 x 4.6 mm. Via Massey (as pyroaurite). Analyzed. The matrix is scalenohedral calcite on dolomite colored dark maroon by hematite. The pointy black things were supposedly hematite but recent (Nov 2021) EDS scans by Joy Desor say that they hetareolite. See the "related" photos and data child images. This material was originally posted as "pyroaurite" (as per the label), and the first SEM_EDS scan appeared to confirm that. Subsequently a second sample was analyzed using much better quality SEM-EDS. The result was "magnesian dolomite". However, it now seems likely that the second sample was - somehow - for the wrong material. See [https://www.mindat.org/photo-320275.html] for more recent data from Joy Desor. Bottom line: The yellowish crystals are iowaite - not pyroaurite or dolomite. ”

“FOV 1.1 x 1.4 mm. This is a child stereo pair. ”

“FOV 4.6 x 7.0 mm. This is a child stereo pair. ”

“FOV 1.0 x 1.3 mm. Xl 0.7 mm. Analyzed. This has now (Nov 2021) been “definitively” identified as hetaerolite via new SEM-EDS and Raman by Joy Desor. (Child images: [https://www.mindat.org/photo-1004716.html ]; [https://www.mindat.org/photo-1179848.html].) It is associated with iowaite (also verified – see [ https://www.mindat.org/photo-320275.html]) and calcite scalenohedra on a matrix of dolomite colored deep maroon by hematite (also verified). Originally posted as zinc rich pyrochroite, based on a too hasty interpretation of a “quick & dirty” SEM-EDS scan. (Child image. Direct link [https://www.mindat.org/photo-1004716.html].) The realization that this was probably hetaerolite was triggered by Travis Olds' post of suspiciously similar hetaerolite (EDS verified) from Michigan: [https://www.mindat.org/photo-1155443.html]. In retrospect, it seems that we (both the analyst and I) did not give enough credence to the Zn peak shown in that SEM-EDS scan. Taking into account that the equipment used detected Zn less readily than Mn, that scan is actually quite consistent with hetaerolite. We probably failed to consider Zn both because the habit is atypical for Franklin/Sterling Hill hetaerolite, and because a very experienced "Franklin" collector had suggested pyrochroite. But Travis' photo showed that this sort of habit for hetaerolite is certainly possible – as has now been verified for this specimen as well. This is a complex but tiny crystal. The resolution of my scope isn't really up to the task. But the ID has now been confirmed - to the extent possible - via SEM- EDS, and the morphology is very interesting. ”

“This is the parent photo rotated 90 degrees. It shows a complex but tiny crystal of hetearolite . The resolution of my scope isn't really up to the task. ”

“This is a stereo version of the parent photo. If you can fuse the images, the combined image will look sharper than either image alone and the morphology will be clearer. ”

“Update Nov 2021: Per SEM-EDS and Raman by Joy Desor (see sibling images), this is indeed hetaerolite. Update July 2021: Given the similarity of the branching crystal to those shown in Travis Olds' photo [ https://www.mindat.org/photo-1155443.html], it is likely that the original interpretation as "zincian pyrochroite" was probably wishful thinking. (Travis agrees that hetaerolite is more likely.) ”

“I’m not very familiar with Raman scans, but – apart from one unexplained peak in the sample scan – this seems like a good match with hetaerolite. ”

“The average At % of two probes is: Mg 1.88% Mn 70.20% Fe 2.96% Zn 24.96% Based on the ideal formula we would expect Mn 66.67% Zn 33.33% Taken literally, even if one lumps Zn with Fe and Mg, there isn’t quite enough (Zn, ...) and a bit too much Mn. But this isn’t SEM-WDS for a polished (etc) sample. Despite the accuracy implied by all those decimal palaces, we can’t really expect anything mote accurate than +- 10-20% (or more – depending in the element). So this is actually a “good-as-can-be expected” match for hetaerolite. In any case, it isn’t pyrochroite – Zn enriched or not. The Raman scan [https://www.mindat.org/photo-1179848.html] is also a good match for hetaerolite (modulo one unexplained peak in the sample scan). ”

“FOV 1.787 mm horizontal. Xl 0.683 x 0.312 mm. This photo is courtesy of Joy Desor. It is just single focus (not stacked), but it useful because it appears to be the same crystal as shown in the parent photo and thus provides very precise dimension for that crystal. (It also confirms that Joy analyzed what I wanted analyzed.) ”

“FOV 1.025 x 1.3 mm. Xl 0.35 mm. Analyzed. This is a stereo child photo showing several tiny crystals of hetaerolite along with several bright yellow crysyals of iowaite. For the iowaite ID data see under [https://www.mindat.org/photo-320275.html]. ”