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A QFL diagram or QFL triangle is a type of ternary diagram that shows compositional data from sandstones and modern sands, point counted using the Gazzi-Dickinson method. The abbreviations used are as follows: Q – quartz; F – feldspar; L – lithic fragments
This is a list of types of sandstone that have been or are used economically as natural stone for building and other commercial or artistic purposes. Trans-regional [ edit ]
Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula Cu Al 6 (PO 4) 4 8 ·4H 2 O.It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue.
Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks.
They are closely related to sandstones in origin, and exhibit many of the same types of sedimentary structures, such as tabular and trough cross-bedding and graded bedding. [ 1 ] [ 2 ] [ 3 ] Fanglomerates are poorly sorted, matrix-rich conglomerates that originated as debris flows on alluvial fans and likely contain the largest accumulations of ...
In 1979, Gemstones Corporation of Pakistan was established to develop the gemstones sector in Pakistan, however in 1997 the corporation liquidated. [3] Now a number of organizations are working in this sector including All Pakistan Commercial Exporters Association of Rough & Unpolished Precious and Semi Precious Stones (APCEA) and Pakistan Gems and Jewellery Development Company (PGJDC).
The sequence is made up of 22 m thick cycles, each with a basal erosion surface followed by dark grey shales with desiccation cracks, planar cross-bedded sandstones with wave rippled tops, overlain by trough cross-bedded micaceous sandstones. These cycles are thought to represent repeated progradation of deltas into a lake.
Kurkar is the regional name for an aeolian quartz sandstone with carbonate cement, [3] in other words an eolianite or a calcarenite (calcareous sandstone or grainstone), found on the Levantine coast of the Mediterranean Sea in Turkey, [3] Syria, Lebanon, Israel, [4] the Gaza Strip [5] and northern Sinai Peninsula. [6]