Bigida,
You probably can't identify the inclusions
optically or on the microprobe, but something has
to be scattering the light. Blue quartz is also
found in granitic gneisses. It is not clear to
me what the relation to mylonites may represent.
eric
>Dear Eric, David and Robert:
>
>
>
>I have read the paper about the llanite (a
>Precambrian rhyolite with blue quartz
>phenocrysts), but this rock is quite different
>from the lithologies I am working with.
>
>I found blue quartz mainly in metagranitoids and
>quartz veins, but restricted to ductile shear
>zones that affect these rocks. The fact that
>calls my attention is the close relationship
>between blue quartz and mylonitization. Neither
>microscopic observations nor electron microprobe
>analyses in the quartz veins, indicate presence
>of rutile and/or ilmenite inclusions.
>
>
>
>Yours. Bígida
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