Compact Phosphate of Lime or Phosphorite Enlarge
[Undated]
Exotic Mineralogy
CXXIV
Calx phosphata, (var)

Compact Phosphate of Lime or Phosphorite

  • Syn.
    • Phosphorite. Werner.
    • Gemeiner Phosphorit. Hausm. s. 123. Karsten, s. 52.
    • Chaux phosphatée Terreuse. Haüy, II. 239. Tabl. 8.
    • Apatite, γ, massive. Aikin, 172.

The Spanish massive variety of Phosphate of Lime has been known many years, and valued for its phosphorescent quality when heated: if closely examined it is found to be composed of dull luminæ arranged in the form of feathers, or diverging from numerous lines branching through the mass, but betrays no external character that would lead any one to consider it related to the crystallized Phosphate or Apatite, although its analysis shews it to be essentially the same. It is found in a considerable bed near Lagrofan, in Estremadura, Spain. Another variety is found at Schlackenwald in Bohemia; it is vessicular, in some parts semitransparent, and appears to be composed of irregular crystals collected together into a mass; among them some traces may be perceived of the hexahedral prism. Pulverulent Phosphorite has been found at Marmarosch, near Sigeth, in Hungary, and I have been told in some part of England, but I cannot learn where.

Pelletier and Donadei have given the following analysis of the variety from Estremadura, which shews it has some admixture, as is commonly the case with amorphous substances:

Lime 59   
Phosphoric acid 34   
Fluoric acid 2.5
Carbonic acid 1   
Muriatic acid 0.5
Silex 2   
Iron 1   
100.0

The pulverulent variety from Hungary gave Klaproth the following ingredients:

Lime 47    
Phosphoric acid 32.25
Fluoric acid 2.5  
Silex 0.5  
Oxide of Iron 0.75
Water 1    
Quartz and argillaceous matter 11.5  
Loss 4.5  
100.0
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