When the potassium feldspar phenocrysts in porphyritic porphyritic rocks, like in form, often with a plate, plate columnar euhedral crystals.
当钾长石在斑状、似斑状岩石中构成斑晶时，常呈板状、板柱状自形的晶体。
2
Under scanning electron microscope, barite in these samples occurs as euhedral crystal, co-existing with authigenic quartz and albite with the same idiomorph.
扫描电镜观察发现，重晶石均为完整自形晶，并与同为自形的石英及钠长石共生。
3
The former are mainly developed in the coarsesilt grained, euhedral and semi-euhedral crystalline calcitic dolomites occurring in the lower part of the first member of the Doushantuo Formation.