Rick Turner's Photo Gallery
1WA-79NMereheadite Pb47Cl25(OH)13O24(CO3)(BO3)2 , Mendipite Pb3Cl2O2 , Hydrocerussite Pb3(CO3)2(OH)2 , Paralaurionite PbCl(OH)
Field of View: 6 mm
This is a fragment of the original specimen of the material described by Dunn and Rouse (in Neues Jahrbuch fur Mineralogie, Monatshefte 1990, 337-342)which was kindly provided by the Smithsonian Institution.
It is actually mereheadite, despite the color, and both chemically and structurally identical to mereheadite from the type locality, Merehead Quarry.
We analysed this (XRD, precision X-ray, EDX) as part of our ongoing study into the structures and mineralogy of Pb-oxyhalides, which grew out of our work on the mineralogy of the Mendip Hills (where Merehead Quarry is located).
There is no sulphate anywhere in this piece (!), so symesite is not present on it, but (a) Pete Dunn would not have made an error, particularly of that magnitude, and (b) mereheadite and symesite are very (very) closely related, so I have no doubt that it is probably present at the locality, but I/we cannot confirm that unambiguously from this specimen.
Also on the specimen are mendipite and hydrocerussite, and yellow paralaurionite (which is out of sight in this image, as it is on the underside).
ULG-GATBradaczekite NaCu4(AsO4)3 , Johillerite Na(Mg,Zn)3Cu(AsO4)3
Field of View: 5.0 mm
The purple-blue mineral in this image bradaczekite, and the abundant small violet spots scattered all over it are johillerite. You will need to view the high resolution version of the image to see the johillerite clearly - there is a lot of it, but individual 'spots' are very small.
The white mineral as well as the dark grey material are as yet still unidentified.
Self collected from the summit fumarole field of the second scoria cone in July 2014.
7U7-6VUParalammerite Cu3(AsO4)2
Field of View: 5.0 mm
The abundant green ball like aggregates shown in this image have just been confirmed (xrd, edx) to be lammerite-beta.
There are (at least) three other minerals on the piece - the bright green ball like mass near top right is most likely to be popovite, and the fibrous green material is probably alumoklyuchevskite, but these are still under investigation so need confirming. There is also an unknown sky-blue mineral 'hiding' in a couple of small cavities on the specimen.
Self-collected in July 2014 from the main fumarole field at the summit of the 2nd scoria cone.
WKN-LRCKarpovite Tl2VO(SO4)2(H2O) , Bobjonesite (V4+O)(SO4)·3H2O , Evdokimovite Tl4(VO)3(SO4)5(H2O)5
Field of View: 2 mm
White needles of evdokimovite with dark blue bobjonesite and light blue karpovite. Fov approx 2mm wide. All species identified by xrd and probe.
Photo used in the original publication (Siidra et al., 2014).
This is the second world locality for bobjonesite.
FVK-A6GEvdokimovite Tl4(VO)3(SO4)5(H2O)5
Minute but abundant white needles of evdokimovite. FoV approx 4mm wide. Identified by probe and xrd.
V3A-1PXShcherbinaite V5+2O5 , Markhininite TlBi(SO4)2 , Pauflerite (V4+O)SO4
An exceptionally rich specimen covered with unusually large yellow-brown needles of shcherbinaite. FoV approx 5mm wide, so the largest needles are up to about 1mm in length.
The white to transparent crystals visible at the base of some of the needles are markhininite, and the pearly looking pale greenish-white xl just in from the middle of the right edge is pauflerite. There is a second, smaller xl of pauflerite just in from the center of the bottom edge.
All the minerals on this specimen have been identified by both probe and XRD - this is from the material used to describe pauflerite.
WK4-Y28Powellite Ca(MoO4) , Parauranophane Ca(UO2)2(SiO3OH)2·5H2O
A 2mm brown crystal of powellite, on a bed of typical Rossing beta-uranophane crystals. This specimen - along with two others - was found at Rossing in 1979.
The occurrence of powellite at Rossing was never formally written up, and as far as I know, these are the only three specimens ever found there (and I have no idea what has happened to the other two since 1979).
The identity has been confirmed by XRD and by EPMS (probe) analysis.
673-9RLGallite CuGaS2 , Germanite Cu13Fe2Ge2S16 , Reinerite Zn3(AsO3)2
Thin grey veinlets of gallite in germanite - the latter oxidised to a nice dark purple color, making the gallite easily visible. There is a small amount of renierite in the specimens too and this has oxidised to a sort of speckled salmon pink color - best seen in the left hand specimen of the two, in the center where there is a sort of downward sloping triangular area just above the veinlet of gallite.
FoV about 100mm, just in case you cant see the ruler...
QH0-065Macphersonite Pb4(CO3)2(SO4)(OH)2
Two large pieces of macphersonite from Tsumeb, dating from the early 1980's. The right hand piece is about 30mm in each dimension, and the larger around 55*30*20 mm.
This is the only time I have seen macphersonite from Tsumeb, and these (plus two other similar bits that I also have) are by far the largest specimens that I have seen from anywhere.
The white powdery mineral on the right hand piece does not match anything in the powder diffraction file, so is quite likely to be another new phase - I would expect that it is most likely to be some type of Pb oxy/hydroxy-carbonate mineral as it seems to have derived from the in-situ alteration of the macphersonite.
1D8-M39Rumseyite Pb2OClF , Hydrocerussite Pb3(CO3)2(OH)2 , Diaboleite Pb2CuCl2(OH)4
The only known specimen of rumseyite, which is the pinkish-beige mineral in the small cavity in the centre. The pseudo-cubic nature of the crystals can be seen, particularly in the top left part of the specimen. This specimen is the holotype for the species.
The matrix is hydrocerussite, and the small light blue area at the 11 o'clock position on the rumseyite is a minute crystal of diaboleite.
Externally, the enclosing hydrocerussite specimen is typical of the material that was widely collected from the #2 vein at Merehead in the early 1970's.
FoV approx 5mm.
Mindat.org Photo of the Day - 9th Jun 2013
