Montebrasite gallery

MONTEBRASITE Gallery Return to Montebrasite page. Click on image for larger view

MONTEBRASITE Palermo Mine, N. Groton, NH 10 mm field of view. Triclinic, truncated, pyramids of grayish montebrasite.	Species: MONTEBRASITE Locality: Palermo Mine, N. Groton, NH Specimen Size: 10 mm field of view. Triclinic, truncated, pyramids of grayish montebrasite. Field Collected: Clayton Ford, A gift from Gordon Jackson Catalog No.: u2011 Notes: A polished grain EDS analysis (BC139) indicated an aluminum phosphate, (EDS carbon response is due to carbon coat). Chemistry and crystalography are a better fit for montebrasite LiAlPO₄(OH,F) than for augelite, the other Al-P candidate. The white spiky clusters are believed to be type 3 goyazite.
MONTEBRASITE Chandlers Mill Mine, Newport, NH 8 mm field of view. A pair of flat, angular, milky, montebrasite crystals	Species: MONTEBRASITE Locality: Chandlers Mill Mine, Newport, NH Specimen Size: 8 mm field of view. A pair of flat, angular, milky, montebrasite crystals Field Collected: Tom Mortimer Catalog No.: 1611 Notes: These crystals are on a specimen with ruifrancoite, a roscherite group mineral. Montebrasite confirmed by polished grain EDS analyses (BC378 set 28) and Raman spectroscopy. Montebrasite chemistry is LiAlPO₄(OH,F). Note, EDS cannot detect lithium.
MONTEBRASITE Chickering Mine, Walpole, NH 2.5 cm specimen	Species: MONTEBRASITE Locality: Chickering Mine, Walpole, NH Specimen Size: 2.5 cm specimen Field Collected: Tom Mortimer Catalog No.: 1475 Notes: This specimen passed both of the tests described in Fred Pough's Field Guide for lepidolite: it fuses easily and the resultant bubbly glass is fluorescent. I have had this specimen on my web site and in my NH display as lepidolite since its inception. A 2023 polished grain EDS analyses showed an absence of potassium, a requirement for most all mica minerals. The chemisrtry computed from the analysis was a very good match for montebrasite. Montebrasite also fuses easily and the resultant bubbly glass is fluorescent. I was fooled on this one.
MONTEBRASITE Chickering Mine, Walpole, NH 4.5 cm specimen MONTEBRASITE Chickering Mine, Walpole, NH 5 mm flake with fused right edge	Species: MONTEBRASITE Locality: Chickering Mine, Walpole, NH Specimen Size: 4.5 cm specimen Field Collected: Tom Mortimer Catalog No.: 2177 Notes: Originally thought these pearly plates were lepidolite, due to easy fusability, second photo. A Raman analyses (scan 314, 315 vs. RUFF reference plot) was a good match for montebrasite. An EDS analyses also supported a montebrasite identification, a simple Al, P mineral, (Li not detectable by EDS). Montebrasite is also easily fusable.
MONTEBRASITE Palermo Mine, Groton, NH 0.5 mm crystal group MONTEBRASITE form	Species: MONTEBRASITE Locality: Palermo Mine, Groton, NH Specimen Size: 0.5 mm crystal group Field Collected: Walter Lane material Catalog No.: A Bob Wilken specimen and photo Notes: [bw] "Practically all of the montebrasite photos on Mindat.org are of single crystal, non-micro variety. This little cluster must have been formed as a secondary recrystallization of the primary montebrasite. I've attached a screenshot of the triclinc (montebrasite) and monoclinic (augelite) crystal forms. You can see the elongate and off-kilter nature of the triclinic from. If you take one of such forms, stand it vertically, and pack others around it, you have a representation of that little cluster."
MONTEBRASITE Palermo Mine, Groton, NH 0.7 mm crystals	Species: MONTEBRASITE Locality: Palermo Mine, Groton, NH Specimen Size: 0.7 mm crystals Field Collected: Walter Lane material Catalog No.: A Bob Wilken specimen and photo Notes:
MONTEBRASITE Palermo Mine, Groton, NH 1.3 mm crystal group	Species: MONTEBRASITE Locality: Palermo Mine, Groton, NH Specimen Size: 1.3 mm crystal group Field Collected: ex. Fred Wilda Catalog No.: A Bob Wilken specimen and photo Notes:
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