Brazilianite
Brazilianite, NaAl3(PO4)2(OH)4: monoclinic, chartreuse-yellow to yellow-green, hardness 5.5, density 2.98. Formula check, localities and pegmatite neighbours.
Brazilianite is a sodium aluminium phosphate, NaAl3(PO4)2(OH)4 on the IMA list (G, 1945, Brazil): monoclinic, chartreuse-yellow to yellow-green, in equant or spearhead-shaped crystals to 20 cm, hardness 5.5, density 2.98, with one good cleavage and a conchoidal fracture. It is named for Brazil, the country where it was first found.
In short
- The species. The Handbook of Mineralogy sheet gives a monoclinic phosphate in equant or spearhead-shaped crystals elongated along [100], to 20 cm, also radial fibrous or globular; cleavage {010} good; fracture conchoidal; hardness 5.5; density 2.98; chartreuse-yellow, pale yellow or yellow-green; streak white. The September 2026 IMA-CNMNC Master List writes NaAl3(PO4)2(OH)4, status G, 1945, Brazil.
- The formula check. Worked on standard atomic weights NaAl3(PO4)2(OH)4 weighs 361.90 and gives P2O5 39.22, Al2O3 42.26, Na2O 8.56 and H2O 9.96 wt%: the sheet’s ideal column to the hundredth. With the cell (a 11.229, b 10.142, c 7.098 Å, β 97°41′, Z 4) it gives a density of 3.001, against the sheet’s 2.998 calculated and 2.98 measured.
- The associate ledger. A 20.00 g brazilianite reads 13.29 g in water. Of the eight phosphates its sheet names as associates or that share amblygonite’s IMA formula pattern, augelite reads lighter (12.58 g), montebrasite ties (13.29 to 13.42 g), and apatite, whitlockite, amblygonite, lazulite, scorzalite and bertossaite read heavier (13.42 to 13.99 g).
- Documented failure: the montebrasite tie. Montebrasite’s measured density starts at 2.98, brazilianite’s figure, and its hardness 5.5 to 6 overlaps. Weight cannot separate them; cleavage can. Brazilianite prints one good cleavage and a conchoidal fracture; montebrasite prints a perfect, a good and a distinct cleavage, pearly on cleavages, and it is triclinic.
- Where. In Brazil, the Córrego Frio and nearby pegmatite mines near Linópolis, and São Geraldo do Baixio, Minas Gerais; Paraíba and Rio Grande do Norte. In the USA, the Palermo #1, Fletcher and G.E. Smith mines in New Hampshire, the Bell Pit at Newry, Maine, and the White Picacho district, Arizona. Also Yukon, Rwanda, Austria, Czech Republic, Italy and Germany.
| Species | IMA formula | System | Hardness | D(meas.) | 20.00 g in water | Cleavage as printed | Colour as printed (abridged) |
|---|---|---|---|---|---|---|---|
| Brazilianite | NaAl3(PO4)2(OH)4 | Monoclinic | 5.5 | 2.98 | 13.29 g | {010} good; fracture conchoidal | Chartreuse-yellow, pale yellow, yellow-green |
| Augelite | Al2(PO4)(OH)3 | Monoclinic | 4.5–5 | 2.696 | 12.58 g | {110} perfect; {201} good; {001}, {101} imperfect | Colourless to white, may be yellowish to pale rose, greenish |
| Montebrasite | LiAl(PO4)(OH) | Triclinic | 5.5–6 | 2.98–3.04 | 13.29–13.42 g | Perfect {100}; good {110}; distinct {011} | Pale brown, pink, pale yellow, gray, white, colourless |
| Amblygonite | LiAl(PO4)F | Triclinic | 5.5–6 | 3.04–3.11 | 13.42–13.57 g | {100} perfect; {110} good; {011} distinct; {001} imperfect | Milk-white, pale yellow, beige, salmon-pink, pale green, pale blue, gray |
| Fluorapatite (apatite) | Ca5(PO4)3F | Hexagonal or monoclinic | 5 | 3.1–3.25 | 13.55–13.85 g | Poor on {0001} and {10-10} | Sea-green, violet, purple, blue, pink, yellow, brown, white |
| Bertossaite | Li2CaAl4(PO4)4(OH)4 | Orthorhombic | 6 | 3.10 | 13.55 g | {100} good | Pale pink |
| Whitlockite | Ca9☐Mg(PO3OH)(PO4)6 | Hexagonal | 5 | 3.12 | 13.59 g | None printed | Colourless, white, gray, yellowish |
| Lazulite | MgAl2(PO4)2(OH)2 | Monoclinic | 5.5–6 | 3.122–3.240 | 13.59–13.83 g | Poor to good on {110}; indistinct on {101} | Azure-blue, sky-blue, bluish white, yellow-green, blue-green |
| Scorzalite | Fe2+Al2(PO4)2(OH)2 | Monoclinic | 6 | 3.33 | 13.99 g | {110} good; {101} indistinct | Dark blue |
What is brazilianite? A yellow-green pegmatite phosphate
Brazilianite is a sodium aluminium hydroxyl phosphate that forms in the phosphate-rich zones of granite pegmatites. The Handbook of Mineralogy brazilianite sheet calls it “a hydrothermal mineral in phosphate-rich zones of granite pegmatites; also in metamorphosed sedimentary deposits”. It is monoclinic, point group 2/m, space group P21/n. Crystals are typically equant, or spearhead-shaped and elongated along [100], with large {011} and {-111}, to 20 cm; it may also be radial fibrous or globular.
Physical and optical properties. Cleavage {010} good; fracture conchoidal; brittle; hardness 5.5; measured density 2.98, calculated 2.998. Chartreuse-yellow, pale yellow or yellow-green, colourless in transmitted light; streak white; lustre vitreous; transparent. Biaxial (+), α 1.602, β 1.609, γ 1.621 to 1.623, 2V(calc.) 71° to 75°, dispersion r < v, faint. The sheet prints no luminescence (ligature-aware search, positive controls hemimorphite and willemite), and the International Gem Society brazilianite article gives its luminescence as none. Hardness testing is on how to test mineral hardness properly.
Name and date. The sheet says it is named for Brazil, the country in which it was first found, and puts type material at the National Museum of Natural History, Washington, D.C., 105048; it marks no type locality. The IMA list gives 1945, Brazil, first reference American Mineralogist 30 (1945), 572. The IGS article says it was discovered in Brazil in 1944; the IMA year is the year of the description.
Brazilianite formula and composition: the formula check
The IMA and Handbook formulas are the same, and the sheet’s ideal column reproduces exactly. NaAl3(PO4)2(OH)4 weighs 361.90 on standard atomic weights: 6.35% sodium, 22.37% aluminium, 17.12% phosphorus. As oxides that is P2O5 39.22, Al2O3 42.26, Na2O 8.56 and H2O 9.96 wt%, the figures the sheet prints in its column (2) to the hundredth. The charges balance: one Na+ and three Al3+ give +10 against two phosphates and four hydroxyls at −10.
The analysed brazilianite. Column (1), from “[Córrego Frio mine,] Brazil” (the brackets are the sheet’s), gives P2O5 37.97, Al2O3 43.82, Na2O 8.42, K2O 0.37, H2O 9.65. Worked to cations per two phosphorus: Al 3.21, Na 1.02, K 0.03, H 4.01. The aluminium runs about 7% above the formula’s 3; the sheet does not comment, and nor does this page.
The cell. a 11.229, b 10.142, c 7.098 Å, β 97°41′, Z 4 gives a volume of 801.10 Å3 and, with the formula, a density of 3.001: 0.003 above the sheet’s calculated 2.998 and 0.02 above the measured 2.98. A 20.00 g piece reads 13.29 g in water at 2.98; the method is on how to measure specific gravity at home.
What does brazilianite grow with, and what does it look like next to them?
The sheet names three settings, and most of the associates it names are phosphates. Muscovite, albite, apatite and tourmaline at Córrego Frio, Brazil; whitlockite, apatite and quartz at the Palermo #1 mine, New Hampshire; amblygonite, lazulite-scorzalite, augelite, bertossaite and apatite in the Buranga pegmatite, Rwanda. Background on the silicates is on muscovite and tourmaline; the apatite group on apatite; and lazulite on is lazulite the same as lapis lazuli.
The associate ledger. Read from each species’ own sheet, a 20.00 g brazilianite at 13.29 g in water sits low among them. Augelite reads 0.71 g lighter. Amblygonite, from 13.42 g, and fluorapatite, from 13.55 g, read heavier, and so do bertossaite, whitlockite and lazulite; scorzalite, at 13.99 g, is 0.70 g heavier. Hardness adds little, 4.5 to 6 across all of them, and colour helps only against scorzalite, which prints dark blue: lazulite’s list is mostly blues but includes yellow-green, and brazilianite’s sheet prints only yellows and yellow-green.
Documented failure: the montebrasite tie. The brazilianite sheet names amblygonite. The IMA list has both LiAl(PO4)F (amblygonite) and LiAl(PO4)(OH) (montebrasite), and montebrasite’s measured density, 2.98 to 3.04, begins exactly at brazilianite’s 2.98; its colours include pale yellow. A weight reading of 13.29 g fits either. The sheets separate them by cleavage: brazilianite prints one good cleavage on {010} and a conchoidal fracture; montebrasite a perfect {100}, a good {110} and a distinct {011}, pearly on cleavages, with microscopic polysynthetic twinning, in a triclinic crystal. A cleavage reading is described on cleavage or fracture.
Where is brazilianite found? The sheet’s localities
The sheet’s Distribution opens in Brazil. The Córrego Frio and other nearby pegmatite mines, Divino das Laranjeiras, near Linópolis, and São Geraldo do Baixio, Minas Gerais; Alto Patrimônio, near Pedro Lavrada, Paraíba; Boqueirão del Parelhas and Alto do Giz, Rio Grande do Norte. In the USA: the Palermo #1 and Fletcher mines, near North Groton, and the G.E. Smith mine, Newport, New Hampshire; the Bell Pit, Newry, Maine; the White Picacho district, Arizona. The Big Fish River–Rapid Creek area, Yukon, Canada; the Buranga pegmatite, Rwanda; Millstätter Seenrücken, Carinthia, Austria; Dolní Bory, Czech Republic; Giogo di Toirano, Savona, Italy; Hagendorf, Bavaria, Germany. The sheet names no British locality.
As a gem. The International Gem Society brazilianite article calls brazilianites primarily collector’s gemstones, and lists cut stones in museum collections, among them 41.9 and 17.0 carats (yellow, Brazil) at the Smithsonian Institution. It gives specific gravity 2.980 to 2.995 and hardness 5.5, which agree with the sheet. The sheet says crystals reach 20 cm; IGS says crystals from Brazil range up to 12 × 8 cm. This page gives no jewellery or care advice.
Other pegmatite phosphates on this site. triphylite is the primary lithium iron phosphate of the same kind of pegmatite, and eosphorite and childrenite are aluminium phosphates from them too. The reference section continues at the species index. We hold no catalogue and nothing here is offered for sale; the wanted list is the only commercial route.