Humite (mineral group)

The humite group[1] is a group of nesosilicates with the general formula A
n
(SiO
4
)
m
(F,OH)
2
.

When A is predominantly magnesium we have the humite subgroup:

The manganese-humite subgroup has members

and the leucophoenicite subgroup has members

Chondrodite is the most common member of the humite group. It may contain Ti up to 9.6% TiO
2
. Chondrodite from Sterling Hill Mine and Franklin Mine contains zinc to 11.5% ZnO and Mn to 36% MnO, and grades to alleghanyite.

The humite minerals commonly alter to serpentine or Mg-rich chlorite and dissolve by weathering, leaving iron oxide residues.[2]

References

  1. Gaines et al (1997) Dana's New Mineralogy Eighth Edition, Wiley
  2. Phillips, W R and Griffen, D T (1981) Optical Mineralogy, pages 142 to 144
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