Mineral Information and Data:

Aldermanite
Mg5Al12(PO4)8(OH)22 • 32H2O [CNMNC approved formula]

Named for Arthur Richard Alderman (1901-1980), Mineralogist and petrologist, University of Adelaide, SA, Australia.

IMA status : Approved Species 1981 (IMA1980-044)
CLASSIFICATION 
Dana
(8th edition) :
42.13.01.01  
  (42) Hydrated Phosphates Containing Hydroxyl or Halogen
  (42.13)
  (42.13.01)
  
Nickel-Strunz
(10th edition) :
08.DE.35
  (08) Phosphates, Arsenates, Vanadates
  (08.D) Phosphates, etc
  (08.DE) With only medium-sized cations, (OH, etc.):RO4 = 3:1
  
Crystal system: Orthorhombic System
Point group (H-M): Unknown — Unk
Unit cell: a = 15.000 Å, b = 8.330 Å, c = 26.60 Å
Crystal Habit: Talc-like flakes
  
Color: Colorless
Diaphaneity: Translucent to transparent
Luster: Pearly
Hardness (Mohs): 2
Measured Density: 2.15 (calculated) g/cm3
Streak: White
  
Geologic Setting: As a secondary mineral in cavities in a brecciated metamorphosed sedimentary phosphate deposit, formed by the alteration of fluellite (Moculta quarry, Australia).
Mineral Association: Fluellite
  

 

Aldermanite
White, blocky aldermanite crystals to 2mm completely covering one face of matrix with colorless prismatic Minyulite crystals in sprays to 3mm.
Origin: Tom's Phosphate quarry, Kapunda, South Australia, Australia.
Sample size: 2 x 1.5 x 2 cm.
Photo: Tom Loomis

<<< BACK TO MINERAL SEARCH