Hureaulite from the Cigana Mine, Conselheiro Pena, Minas Gerais, Brazil. Specimen size 2.8 cm. Photo Copyright © Strickja

Chemical Formula: (Mn,Fe)5(PO4)2(HPO4)2·4H2O
Locality: Hureaux in St. Silvestre and Vilate near Chanteloube, N of Limoges, Haute Vienne, France.
Name Origin: Named for the locality.
Hureaulite is a manganese phosphate with the formula (Mn,Fe)5(PO4)2(HPO4)2·4H2O. It was discovered in 1825 and named in 1826 for the type locality, Les Hureaux, Saint-Sylvestre, Haute-Vienne, Limousin, France.

A complete series exists from lithiophilite, LiMn2+PO4 to triphylite, LiFe2+PO4, including hureaulite, strengite,  FePO4·2H2O, stewartite, Mn2+Fe3+2(OH,PO4)2·8H2O, and sicklerite, (LiMn2+,Fe3+)PO4.

Physical Properties

Color:  Red, White, Grayish white, Yellowish white, Reddish white.
Density: 3.18
Diaphaneity: Transparent to Translucent
Fracture: Brittle – Uneven – Very brittle fracture producing uneven fragments.
Hardness: 5 – Apatite
Luminescence: Non-fluorescent.
Luster: Vitreous – Greasy
Streak: white

Photos :

Hureaulite Crimonoso Mine, Minas Gerais, Brazil Small Cabinet, 6.1 x 4.4 x 3.2 cm © irocks
Huréaulite Pomarolli, Linópolis, Divino das Laranjeiras, Minas Gerais  Brazil (2006) Specimen size: 4.9 × 4.7 × 4.7 cm = 1.9” × 1.9” × 1.9” Main crystal size: 0.4 × 0.3 cm = 0.2” × 0.1” © Fabre Minerals
Reddingite with Hureaulite Cigana Mine, Galiléia, Doce valley, Minas Gerais, Brazil Specimen weight:85 gr. Crystal size:Up to 6.7 mm Overall size: 70mm x 45 mm x 30 mm © minservice
Hureaulite with Rockbridgeite and Reddingite Jocao Mine – Galileia – Minas Gerais – Brasil Specimen weight:22 gr. Crystal size:Up to 7 mm Overall size: 38mm x 17 mm x 18 mm © minservice
Reddingite on Hureaulite Jocão Mine, Conselheiro Pena, Minas Gerais, Southeast Region, Brazil Thumbnail, 2.3 x 2.3 x 1.7 cm © irocks
Hagendorf South Pegmatite (Cornelia Mine; Hagendorf South Open Cut), Hagendorf, Waidhaus, Vohenstrauß, Oberpfälzer Wald, Upper Palatinate, Bavaria, Germany © Stephan Wolfsried