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The sculpture represents patterns made from a stone skipping over surface of water. Installed as part of the architect’s concept for drainage system as a creek bed.
SKIPPING STONE
Artist: Hew Chee Fong
Type of work: Sculpture
Materials: Black Granite, polished surface
Size: 100 x 100 Year: 2000
Location: Oxley Avenue, Redcliffe Library and Art Gallery
REDCLIFFE ART GALLERY QLD
The three slabs represent a captured moment in time where it appears that a stone has just skipped over the surface of water. On a deeper level, the work is intended to represent the Zen notion that still water (the mind) reflects reality purely; but as soon as a stone (thought) makes ripples, reality becomes distorted.
Granite is a common type of felsic intrusive igneous rock that is granular and phaneritic (coarse-grained) in texture. Granites can be predominantly white, pink, or grey in colour, depending on their mineralogy. The word "granite" comes from the Latin granum, a grain, in reference to the coarse-grained structure of such a holocrystalline rock. Strictly speaking, granite is an igneous rock with between 20% and 60% quartz by volume, and at least 35% of the total feldspar consisting of alkali feldspar, although commonly the term "granite" is used to refer to a wider range of coarse grained igneous rocks containing quartz and feldspar.
The term "granitic" means granite-like and is applied to granite and a group of intrusive igneous rocks with similar textures and slight variations in composition and origin. These rocks mainly consist of feldspar, quartz, mica, and amphibole minerals, which form an interlocking matrix of feldspar and quartz with scattered darker biotite mica and amphibole peppering the lighter colour minerals. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic texture is known as a granite porphyry.
Granitoid is a general, descriptive field term for lighter-coloured, coarse-grained igneous rocks. Petrographic examination is required for identification of specific types of granitoids. The extrusive igneous rock equivalent of granite is rhyolite. Granite is nearly always massive (lacking any internal structures), hard and tough, and therefore it has gained widespread use throughout human history as a construction stone.
Black Granite In the construction industry, black rocks that share the hardness and strength of granitic rocks are known as black granite. In geological terms, black granite might be gabbro, diabase, basalt, diorite, norite and anorthosite.
Gabbro refers to a large group of dark, often phaneritic, mafic intrusive igneous rocks chemically equivalent to basalt. It forms when molten magma is trapped beneath the Earth's surface and slowly cools into a holocrystalline mass.
Diabase is a mafic, holocrystalline, subvolcanic rock equivalent to volcanic basalt or plutonic gabbro. Diabase dikes and sills are typically shallow intrusive bodies and often exhibit fine grained to aphanitic chilled margins which may contain tachylite (dark mafic glass). Diabase is the preferred name in North America, yet dolerite is the preferred name in most of the rest of the world, where sometimes the name diabase is applied to altered dolerites and basalts.
Basalt is a common extrusive igneous (volcanic) rock formed from the rapid cooling of basaltic lava exposed at or very near the surface of a planet or moon. Flood basalt describes the formation in a series of lava basalt flows.
Diorite is an intrusive igneous rock composed principally of the silicate minerals plagioclase feldspar, biotite, hornblende, and/or pyroxene. The chemical composition of diorite is intermediate, between that of mafic gabbro and felsic granite.
Diorite is usually grey to dark-grey in colour, but it can also be black or bluish-grey, and frequently has a greenish cast Norite, also known as orthopyroxene gabbro, is a mafic intrusive igneous rock composed largely of the calcium-rich plagioclase labradorite, orthopyroxene, and olivine.
Norite may be essentially indistinguishable from gabbro without thin section study under the petrographic microscope. The principal difference between norite and gabbro, however, is the type of pyroxene of which it is composed; norite is predominately composed of orthopyroxenes, largely high magnesian enstatite or an iron bearing intermediate hypersthene, whereas the principal pyroxenes in gabbro are clinopyroxenes, generally medially iron-rich augites Anorthosite is a phaneritic, intrusive igneous rock characterized by a predominance of plagioclase feldspar (90–100%), and a minimal mafic component (0–10%). Pyroxene, ilmenite, magnetite, and olivine are the mafic minerals most commonly present.
To the questions:
a) From your observations, how many black granite samples are visible?
b) Describe the sides that are visible
c) What type of "granite" is here?
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