[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]
1/ Andesite
Andesite is a fine-grained, extrusive igneous rock composed mainly of
plagioclase with other minerals such as hornblende, pyroxene and
biotite.
[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]
Andesite: The specimen shown is about two inches (five centimeters) across.
2/
[ندعوك للتسجيل في المنتدى أو التعريف بنفسك لمعاينة هذه الصورة]
Basalt?
Basalt is a dark-colored, fine-grained, igneous rock composed mainly of plagioclase
and pyroxene minerals. It most commonly forms as an extrusive rock, such as a lava flow, but
can also form in small intrusive bodies, such as an igneous dike or a thin sill. It
has a composition similar to gabbro. The difference between basalt and gabbro is
that basalt is a fine-grained rock while gabbro is a coarse-grained rock.