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Scapolite Stone
Chemical Formula: (Na,Ca)4[Al3Si9O24]Cl
Mineral Name: Scapolite
Color: White, colorless, greenish or gray, golden, purple
Hardness: 5.5 - 6.0
Specific Gravity: 2.5 - 2.7
Scapolite, or sometimes called Wernerite, is a grayish white mineral occuring in tetragonal crystals and in cleavable masses. It is essentially a silicate of alumina and soda. The structure of scapolite is similar to some feldspathoids in that it is composed of large open spaces in the framework of silicate and aluminum tetrahedrons. It forms in metamorphic rocks from the alteration of plagioclase feldspars.
Scapolite relates to "shaft" in Greek is tetragonal with a square or octahedral cross-section. It is difficult to identify scapolite minerals from each other as they differ slightly in density and index of refraction. Due to this closeness in properties and yet seemingly very different chemistries, scapolite has had its share of pseudonyms.
It is very popular owing to the bright colors of its gemstones. The less transparent material can be cut as cabochons. Rutilite is found in the regions of New Jersey, New York in USA; Norway; Mount Vesuvius, Italy and Mexico, Brazil, Madagascar, Tremorgio, Switzerland and Burma.
