I’m looking for precise
(crystal system, chemical composition, color, hardness, specific
gravity, refractive index, dispersion and pleochroism) concerning the
following stones : Bytownite, Clinohumite, Ekanite, Eosphorite and
Jeremejevite.
Hello, I managed to track down some of the properties of the
5 minerals you mentioned, perhaps others on Orchid will be able
to add to these?
Eosphorite
Formula: (Mn,Fe)AlPO4(OH)2.H2O
CIM: 19.12.55
CrystalSystem: Orthorhombic
Lustre: Vitreous, Resinous
Colour: Pink, Rose red,
Hardness: 5
SpecificGravity: 3.06 - 3.25
R.I: 1.63 - 1.66 (Biaxial Negative).
See also: Childrenite
Localities: Laura Da Ilha, Itinga, Minas Gerais, Brazil
Taquaral mine, Minas Gerais, Brazil
Rapid Creek area, Yukon Territory, Canada
Eosphorite-Childrenite (in ratios Chl:Eos 80:20 to Chl:Eos 45:55)
widespread. With Wardite, etc. [Mineralogical Record Vol 23 No.4
pp19]
(TL) Branchville, Fairfield Co., Connecticut, USA
Reference “Dana” pg. 732.
---- Jeremejevite
Formula: Al6B5O15(F,OH)3
CrystalSystem: Hexagonal
---- Bytownite
Formula: (NaSi,CaAl)AlSi2O8
CIM: 16.10.1
Localities: ?The Rill, The Lizard, Cornwall, England
J.S.Flett & J.B.Hill 1946 reported a mineral near Bytownite [Golley &
Williams, 1996, 12 - “Cornish Mineral Reference Manual”]
Eycoyy, Cumbria, England
- Clinohumite
Formula: (Mg,Fe)7(SiO4)3(F,OH)2
CIM: 17.1.12
Polymorphs: Humite
Synonyms: Klinohumit
Localities: Parker mine, Notre Dame du Laus, Qu=E9bec, Canada
(TL) Vesuvius, Naples, Italy
[Clark, 1993 - “Hey’s Mineral Index”]
Camas Malag, Isle of Skye, Scotland
[Specimen in the Natural History Museum, London]
Ekanite
Formula: (Th,U)(Ca,Fe,Pb)2Si8O20
CIM: 14.16.16
RI: 1.60
S.G: 3.28
CrystalSystem: Tetragonal
Localities: Mt St.-Hilaire, Qu=E9bec, Canada
(TL) Ehiliyagoda, Ratnapura, Sri Lanka
Regards, Laurie Veska.