黑云辉长岩的英文：
biotite gabbro

So the dark mica in this granite should be called biotite.
那么．在这块花岗岩中的黑色云母类矿物就应当叫做黑云母了。

biotite is a subordinate constituent of the mafic and ultramafic rocks generally
黑云母一般是镁铁质及超镁铁质岩石中的次要成分。

The banded gneisses underlying the mine field are, as a rule, micaceous, the amount of biotite determining mainly the shades of the bands
本矿区的带状片麻岩照例富含云母，黑云母的多少决定片麻岩条带的色调。

The micro-gabbro phase is identical with the typical Bulawayan dolerite sills
微辉长岩相与标准的布拉瓦约粒玄岩床相同。

Even foliated metamorphic rocks and banded gabbro can be curved to form folds.
即使变质岩中的片理以及辉长岩中的条带也可产生弯曲而形成褶皱。