|Minerals of the Chickering Mine Walpole, NH UK_TM1 Back to Chickering front page.|
Specimen owner ID's (capitals): TM = Tom Mortimer, BW = Bob Wilken, BJ = Bob Janules, PC = Peter Cristofono, AW = Anna Wilken
Photographer ID's (lower case).
Identification: Unknown. A Ca, Fe, Mn phosphate
Discussion: First analysis suggested a Ca, Fe phosphate: EDS analysis. Perhaps one of the Jahnsite flavors fit this chemistry?
[tm] 12/16/10 - Querried Kerry Day about a jahnsite fit for this unknown. His reply: "It is a poor fit for Jansite Group which at best has a Ca:P ratio of 1:4. Your Ca ratio is closer to 1:2."
[tm] 12/17/10 - Sent photo of this specimen to Kerry Day. His further reply: "You have essentially a CaFe2P2 mineral. The only possibilities I can think of are Graftonite and Mitridatite. I know they are poor morphological fits. Maybe you have something new.
12/19/10 - Peter Cristofono forwarded two photos that appear to be this unknown. Peter suggested the matrix on his specimen might be rockbridgeite.
2/2/11 [tm] - More photos, UK_TM1_[2,2a,2b], from another specimen. Radial spray from this specimen sent for analysis 2/3/11. Results returned 2/14/11. This second UK_TM1 EDS analysis. was quite different from the one noted above, with almost no calcium and twice the iron content. Kerry Day suggested some similarity to the rockbridgeite plot. Beyond the common radial structure, there are some noteable differences between EDS_set10 TJ2 and UK_TM1_[2,2a,2b]. The color on EDS_set10 TJ2 is much more toward yellow and the individual crystals of EDS_set10 TJ2 are more distinct. Based on the EDS result, this is certainly a different species than the one in the EDS_set10 TJ2 photo here. [tm- I have left this UK in this web page position for time being] perhaps laueite is a best guess for this mineral. Will likely require XRD to solve.