Dear Trisrota,
To my knowledge you have a good chance to discriminate them just looking
at the texture itself and the mineral assemblage. 'Real' spinifex
texture olivine is needle-like or bladed, but most commonly skeletal or
feathery. Spinifex-like or pseudospinifex olivine (metamorphic origen)
is needle-like or bladed, but no skeletal nor feathery. Moreover in the
pseudospinifex there is no glass in the matrix and used to have other
hydrous primary minerals like talc, chlorite and tremolite.
There is a vast literature for the 'real' spinifex texture. For
metamorphic spinifex-like texture you may be referred to Oliver et al.
1972, Evans and Trommsdorff , 1974, Snoke and Calk, 1978, Bakke and
Korneliussen, 1986, Trommsdorff et al. 1998, Padrón-Navarta et al. 2010.
Good luck,
Cheers,
José Alberto Padrón-Navarta
Departamento de Mineralogía y Petrología
Universidad de Granada,
Spain
El 22/06/2011 1:17 PM, Trisrota Chaudhuri escribió:
>
> Dear all,
> Please forgive my ignorance. But can please let me know how to
> demarcate between spinifex textured olivine and aciclar metamorphic
> olivine? Is there any textural or distinct mineral association?
> Best Regards,
> --
> Trisrota Chaudhuri,
> JRF of Indian Statistical Institute and Jadavpur University,
> Kolkata, India.
>
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