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Two splash-form tektites, molten terrestrial ejecta from a meteorite impact. Tektites (from Ancient Greek τηκτός (tēktós) 'molten') are gravel-sized bodies composed of black, green, brown or grey natural glass formed from terrestrial debris ejected during meteorite impacts.
Phyllite Banded gneiss with a dike of granite orthogneiss Marble Quartzite Manhattan Schist, from Southeastern New York Slate. Anthracite – Hard, compact variety of coal; Amphibolite – Metamorphic rock type; Blueschist – Type of metavolcanic rock; Cataclasite – Rock found at geological faults – A rock formed by faulting
The slabs are finished (i.e., polished, honed), then sealed with resin to fill micro-fissures and surface imperfections typically due to the loss of poorly bonded elements such as biotite. The fabricators' shop cuts these slabs down to final size and finishes the edges with equipment such as hand-held routers, grinders, CNC equipment, or polishers.
Decomposed granite is a kind of granite rock that is weathered to the point that the parent material readily fractures into smaller pieces of weaker rock. Further weathering yields material that easily crumbles into mixtures of gravel -sized particles known as grus that further may break down to produce a mixture of clay and silica sand or silt ...
Breccia is composed of coarse rock fragments held together by cement or a fine-grained matrix. [5] Like conglomerate, breccia contains at least 30 percent of gravel-sized particles (particles over 2mm in size), but it is distinguished from conglomerate because the rock fragments have sharp edges that have not been worn down. [6]
Rhomb porphyry is a volcanic rock with gray-white large porphyritic rhombus-shaped phenocrysts of feldspar (commonly anorthoclase) embedded in a very fine-grained red-brown matrix. The composition of rhomb porphyry places it in the trachyte – latite classification of the QAPF diagram .
Biotite is a common group of phyllosilicate minerals within the mica group, with the approximate chemical formula K(Mg,Fe) 3 AlSi 3 O 10 (F,OH) 2.It is primarily a solid-solution series between the iron-endmember annite, and the magnesium-endmember phlogopite; more aluminous end-members include siderophyllite and eastonite.
Augen gneiss, from the German: Augen, meaning "eyes", is a gneiss resulting from metamorphism of granite, which contains characteristic elliptic or lenticular shear-bound grains (porphyroclasts), normally feldspar, surrounded by finer grained material. The finer grained material deforms around the more resistant feldspar grains to produce this ...