Petrographically, these rocks, known as black granites in commercial market, are fine to medium-grained having
ophitic to sub-ophitic texture with plagioclase and clinopyroxene as the major mineral phases, while opaques, quartz, biotite, amphibole, olivine, apatite, chlorite, orthopyroxene and epidote occur as minor to accessory phases.
The Talavera sample shows large anhedral poikilitic orthopyroxene crystals, leading to a hypidiomorphic subophitic to
ophitic texture.
Basalt is medium-grained, with
ophitic texture formed by plagioclase and clinopyroxene and matrix consisting of chlorite, zeolite, Ti-magnetite, titanite, ilmenite, apatite and pyrite.
Bituminous mixtures have an AC 16 S grain-size distribution with
ophitic aggregate and a void percentage that depends on the filler used.
Ophitic basalt predominates In the Aberdare; its radiating crystals of feldspar recall Dandelions in seed.
Phenocryst sequence = olivine, Phenocryst sequence = olivine, augite, plagioclase such that plagioclase, augite locally plagioclase phenocrysts are less yielding
ophitic and subophitic common than in tholeiites.
These zones also control the location of minor bodies of rapakivi in southern Finland and an
ophitic gabbro body (Sigula) in the Tallinn zone.
Texture of the groundmass is most often
ophitic. Examined granodiorite porphyries were also characterized by content of normative minerals (CIPW norm).
Most of the basalts are porphyritic and textures range from very fine-grained to very coarse-grained, using these terms in the volcanic sense (Table 1), and include
ophitic, subophitic, intergranular and intersertal varieties.
The author of our greatest poetic theodicy, moreover, refuses to accept the
Ophitic Gnostic notion that identified the serpent with Christ.
The flow is a coarse-grained,
ophitic basalt containing heavily altered plagioclase and relatively unaltered clinopyroxene.