96Materials libraryBrazilianite: bounded material evidenceA sodium aluminium phosphate with recorded crystals.
Evidence remains bounded by each cited work; no unrecorded specimen is identified.
- Formula
- NaAl3(PO4)2(OH)4
A phosphate with its own structure
The Handbook of Mineralogy identifies Brazilianite as monoclinic NaAl3(PO4)2(OH)4. Its formula has sodium, aluminium, phosphate and hydroxyl. The formula and structure together define the species. Shared phosphate does not make two minerals the same. The reference lists equant crystals, with similar lengths on their main axes, and spearhead forms. Some are long in one direction. Fibrous and globular forms also occur. It has good {010} cleavage, is brittle and has conchoidal fracture, a curved break. It occurs in phosphate-rich parts of granite pegmatites and in metamorphosed sedimentary deposits. Its neighbouring minerals differ by place. Apatite is one neighbour in several examples. It is not another name for this mineral. The handbook says the name honours Brazil.
Evidence: Handbook of Mineralogy: Brazilianite
A heart cut in the Gübelin collection
GIA’s 2011 record concerns Gübelin collection number 33942. This clear heart cut weighs 11.91 carats. Its recorded colour was light, moderately strong greenish yellow. Refractive indices were 1.608 and 1.620. Birefringence was 0.012; specific gravity was 2.99. These measured results concern this stone. They are not promised for every Brazilianite. A microscope showed tiny colourless crystals in a plane near the pavilion. The team saw no pleochroism or absorption features. The stated tests found no ultraviolet fluorescence or phosphorescence. The place, Brazil, Minas Gerais, came from collection records. It is recorded provenance, not a separate proof of origin. No optic-axis diagram was given. This gap limits how fully we can work out its orientation from the record.
Evidence: Brazilianite, Collection 33942
An oval with fluid inclusion patterns
GIA’s 2010 record concerns collection number 33948, an oval of 14.39 carats. It was medium-light, very slightly greyish yellow-green. This is its own dated record, not a copy of the heart’s. Refractive indices were 1.605 and 1.621. Specific gravity was 3.01. The team saw yellow and yellowish green pleochroic colours. It also found broad absorption below 420 nanometres. One colour word would hide these differences. Under magnification, fluid inclusions lay in partly healed fractures. They made a fingerprint pattern. It shows part of the gem’s internal history. It does not name the chemistry of each inclusion. The collection again gives Minas Gerais, Brazil as the place. Neither this label nor the inclusions test another stone’s origin. The ultraviolet findings concern only this oval in the stated examination.
Evidence: Brazilianite, Collection 33948
A cushion and a brief afterglow
GIA’s 2011 record lists collection number 34271. It is a clear greenish yellow cushion of 17.33 carats. Refractive indices were 1.602 and 1.619; specific gravity was 3.01. Long-wave ultraviolet light made a weak yellow fluorescence across the gem. Yellow phosphorescence then lasted several seconds. Short-wave light gave no fluorescence in this test. Both the kind of light and timing matter. Saying all Brazilianite glows would hide this detail. The team saw a colourless mineral inclusion but did not identify it. It also recorded facet reflections. A feature that looks internal need not be a separate, named mineral. The place entry is Divino das Laranjeiras in Minas Gerais, Brazil. It remains recorded provenance. Neither the afterglow nor the unknown inclusion proves origin or treatment history. They cannot identify another stone.
Evidence: Brazilianite, Collection 34271
Crystal forms and a single heating sequence
Čobić and colleagues studied Brazilianite from several places in 2011. They studied crystal shape and used X-ray diffraction. About one hundred crystals were examined. They chose forty-four for goniometric work, which measures face angles, and eleven for diffraction. The survey found twenty forms. Six had not been recorded before for the species. Unequal sample numbers and grooved surfaces limited comparisons between places. A separate test used one greenish yellow Telírio crystal. It went through a series of oven exposures. No colour loss was seen at the lower steps. A little was lost after 200°C. Loss was marked at 250°C and complete after 300°C. Exposure times changed as well as temperatures. This result concerns one crystal. It is not a general damage threshold or a routine trade treatment. Both the shape survey and heat test have limits. Wider claims about the species remain open.
Evidence: Crystal morphology and XRD peculiarities of brazilianite from different localities
Hydrogen positions in an abstract-bounded study
Gatta and colleagues’ 2013 study is described in an institutional abstract. It concerns gem-quality Brazilianite from Telírio. They used electron microprobe, single-crystal X-ray diffraction and neutron diffraction. The chemistry was close to the ideal formula. They describe a three-dimensional framework. Chains of aluminium octahedra link to phosphate tetrahedra. Sodium sits in distorted cavities along [100]. Neutron work asked where the hydroxyl hydrogen atoms lie. The team found five sites. Two were mutually exclusive, each with half occupancy: only one of those positions is filled at a time. Five sites thus do not add a fifth hydrogen to the ideal formula. The abstract also discusses hydrogen bonds and compares wardite. These are the authors’ summary findings. The full paper was not available. Its numerical refinements, detailed uncertainty tables and further arguments are not reproduced or inferred here.
Evidence: Neutron diffraction in gemology: Single-crystal diffraction study of brazilianite, NaAl3(PO4)2(OH)4
Phosphate and hydroxyl vibrations
Frost and Xi’s 2012 author abstract uses Raman and infrared spectroscopy on Brazilianite. It assigns a Raman band at 1019 inverse centimetres to phosphate symmetric stretching. Bands at 973 and 988 inverse centimetres are assigned to HOPO3 stretching. The infrared spectrum was more complex. Several Raman bands were also in the phosphate-bending region. The authors read these results as signs of phosphate and hydrogen-phosphate units in their sample. Hydroxyl stretching bands were at 3249, 3417 and 3472 inverse centimetres. They linked them to nonequivalent hydroxyl environments, where those groups have different surroundings. Such tests ask more than whether phosphate is present. They can ask how units in the structure behave. The full paper was not available. We could not check its full sample account, spectral processing or every qualification. This summary cannot identify another gem on its own.
Evidence: Molecular structure of the phosphate mineral brazilianite NaAl₃(PO₄)₂(OH)₄ – A semi precious jewel
A dated regional context
Barreto and Bittar’s 2010 account places Brazilianite among the minerals of Minas Gerais. It splits Brazil into four gemmological sub-provinces. The eastern one is mainly Minas Gerais and Espírito Santo, with a smaller part of Rio de Janeiro. This dated framework lists pegmatites and hydrothermal veins. It also lists later alluvial, colluvial and older sedimentary concentrations. These can gather material after its first formation. The discussion lists Brazilianite among the less prominent regional gems. Granitic rocks, their pegmatites and hydrothermal deposits are key settings for many gems there. This gives context to a mineral named for a country. Nationality, locality and identity are still different things. The account is broader than a study of this mineral’s deposits. Its general settings cannot prove where each crystal grew. Economic totals, rankings and output figures are outside this profile. It retains historical regional placement, not present-day extraction.
Evidence: The gemstone deposits of Brazil: occurrences, production and economic impact
Sources & reading
- Handbook of Mineralogy: BrazilianiteMineral Data Publishing · 2026-10-06
Study-bound.
- Brazilianite, Collection 33942GIA · 2026-10-06
Study-bound.
- Brazilianite, Collection 33948GIA · 2026-10-06
Study-bound.
- Brazilianite, Collection 34271GIA · 2026-10-06
Study-bound.
- Crystal morphology and XRD peculiarities of brazilianite from different localitiesNatura Croatica · 2026-10-06
Study-bound.
- Neutron diffraction in gemology: Single-crystal diffraction study of brazilianite, NaAl3(PO4)2(OH)4American Mineralogist · 2026-10-06
Study-bound.
- Molecular structure of the phosphate mineral brazilianite NaAl₃(PO₄)₂(OH)₄ – A semi precious jewelJournal of Molecular Structure · 2026-10-06
Study-bound.
- The gemstone deposits of Brazil: occurrences, production and economic impactBSGM · 2026-10-06
Study-bound.
