The chemical formula of mineral Mordenite is indicated by (Ca,Na2,K2)Al2Si10O24 – 7H2O or Hydrated Calcium Sodium Potassium Aluminum Silicate. Mordenite is actually a Silicate mineral. Henry How first described mineral Mordenite in 1864 at Morden, Bay of Fundy, Kings Co., Nova Scotia, Canada. The mineral was named after its type of locality, the small community of Morden. Mordenite is known to crystallize in the orthorhombic system. In optical mineralogy, this orthorhombic crystal system comprises crystals having three mutually perpendicular axes, of which all are of different lengths.
Mordenite is also a known member of the Zeolite Group of minerals. Mordenite is also commonly used as mineral specimen and it is usually found displaying an interesting microscope images when viewed under polarizing light microscope used in optical mineralogy. And just like other zeolite mineral, Mordenite has open channels that allow large ions and molecules to reside and also move around inside the overall framework of the mineral. The size of the ions and molecules are actually controlled by the size of the open channels. And therefore because of this property of zeolites like Mordenite, they can act as chemical sieve, which allows some ions to pass through while blocking others. Mordenite can be also used as chemical filter. Zeolite minerals are so beautiful and they are usually found containing a wide diversity of colors and crystal forms that are commonly majestically exhibited under geological polarizing light microscopes. Mordenite among other Zeolites is considered popular to collect because of their great attraction to mineral collectors. Some Mordenite specimens are very common and easy to collect, while some are extremely rare and are usually a pleasure to finally own. Mordenite is actually a rare zeolite mineral.
Mineral Zeolite is most commonly found colorless, white, yellow, pink and red in color that can be more splendidly exhibited when the mineral section is viewed with the aid of petrographic polarizing light microscopes for mineralogists. Mordenite is usually found showing a vitreous to silky and pearly luster in reflected light of petrographic polarizing microscope used in optical mineralogy. Mordenite is also commonly found having perfect cleavage when viewed under polarizing microscopes for mineralogists. When closely evaluated under polarized microscope, Mordenite is most commonly found exhibiting uneven fracture. The specific gravity measure of the mineral usually gives an approximate value of about 2.1 grams per cubic centimeters, which is considered very light. The hardness measure of the mineral when it is evaluated using the Mohs scale method is usually ranging from 4 to 5. Mordenite is most commonly found leaving a white streak when it is rubbed on a white porcelain streak plate.
Mineral Mordenite is most commonly found forming fine sprays of radial acicular crystal clusters that look like pin-cushions or snowballs that are more splendidly exhibited when viewed under petrographic polarizing light microscopes. Most crystals of mineral Mordenite are found transparent to translucent in appearance. The crystal habits of the mineral Mordenite as described in optical mineralogy usually include sprays of radial acicular crystals clusters that can actually remind someone of pin-cushions or snowballs and they are commonly found splendidly exhibited under polarizing light microscopes. Individual crystals of mineral Mordenite are commonly found prismatic to acicular and are also found striated vertically and these are more clearly exhibited when evaluated under petrographic polarizing light microscopes. Aggregates can be also found radiating, fibrous, columnar and encrusting. Some Mordenite specimens are blocky or in the shapes tend to be equant and some others are found as reniform or kidney-like in shape.
Mordenite is most commonly found exhibiting a moderate surface relief when closely viewed under several adjustments on the aperture diaphragm of the polarized light microscopes for mineralogists. Mordenite has no dispersion display as described in optical mineralogy. Mineral Mordenite is known to exhibit biaxial figure that is both optically positive and negative when closely examined with the aid of the petrographic polarizing light microscope. The maximum birefringence of the mineral is usually 0.005 when examined closely with the aid of the polarizing microscope for geologists. The refractive index of the mineral Mordenite is commonly found ranging from 1.472 to 1.487 when viewed under petrographic polarizing microscope. Crystals of mineral Mordenite are usually found striated or with parallel lines on crystal surface or cleavage face. The radioactivity of the mineral Mordenite is barely detectable. There is no specific data found on the toxicity and health dangers for mineral Mordenite. However, the specimens of the mineral Mordenite should be treated with great care and use of sensible precaution is advised upon handling them.
When found on top of other interesting and wonderful associated minerals, mineral Mordenite can be extremely striking most especially when evaluated with the aid of the polarizing microscopes. Mineral Mordenite is definitely considered as a must have most especially for the dedicated zeolite collectors. Mineral Mordenite is most commonly found associated with other interesting minerals such as quartz, natrolite, calcite, chabazite, stilbite, heulandite, and other zeolites. The best field indicators of mineral Mordenite usually include crystal habit, low density, color and associations. Mordenite commonly forms in cavities in andesitic rocks. It is also found in veins and in amygdaloids in igneous rocks. This mineral species Mordenite notably occurs at several localities including Morden, Kings Co., Nova Scotia, Canada as well as the Hoodoo Mountains, Wyoming and Arizona in the United States and also Val dei Zuccanti in Italy and in Poona, India.
