The ferrierite group of zeolite

Zeolite

Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents. The term zeolite was originally coined in 1756 by Swedish mineralogist Axel Fredrik Cronstedt, who observed that upon rapidly heating the material stilbite, it produced large amounts of steam from water that...

 mineral

Mineral

A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

s (the FER structure) consists of three very similar species: ferrierite-Mg

Magnesium

Magnesium is a chemical element with the symbol Mg, atomic number 12, and common oxidation number +2. It is an alkaline earth metal and the eighth most abundant element in the Earth's crust and ninth in the known universe as a whole...

, ferrierite-Na

Sodium

Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...

, and ferrierite-K

Potassium

Potassium is the chemical element with the symbol K and atomic number 19. Elemental potassium is a soft silvery-white alkali metal that oxidizes rapidly in air and is very reactive with water, generating sufficient heat to ignite the hydrogen emitted in the reaction.Potassium and sodium are...

, based on the dominant cation in the A location. Ferrierites are orthorhombic minerals with highly variable cationic composition, (Na,K)₂Mg(Si,Al)₁₈O₃₆(OH)·9H₂O. Calcium and other ions are often also present. They are found in vitreous to pearly, often radiating, spherical aggregates of thin blade-shaped transparent to translucent crystals.

Ferrierite typically occurs as an alteration mineral in basalt

Basalt

Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic rocks and in tuff

Tuff

Tuff is a type of rock consisting of consolidated volcanic ash ejected from vents during a volcanic eruption. Tuff is sometimes called tufa, particularly when used as construction material, although tufa also refers to a quite different rock. Rock that contains greater than 50% tuff is considered...

aceous sediments. In North America, it is found at Kamloops Lake, BC, Canada

Kamloops Lake

Kamloops Lake in British Columbia, Canada is situated on the Thompson River just west of Kamloops. The lake is 1.6 km wide, 29 km long, and up to 152 m deep...

 (the original Type locality) and Leavitt Lake, California. Ferrierite was named for Canadian geologist and mining engineer Walter Frederick Ferrier

Walter Frederick Ferrier

Walter Frederick Ferrier was a Canadian geologist and mining engineer.He graduated from McGill University’s school of mining engineering. He was a tireless mineral collector and was known for walking straight into mining offices to request specimens. Consequently, he created large collections of...

 (1865-1950).

Use

Synthetic ferrierites have even greater cation variability and have important uses as commercial filters and ion-exchange beds.

Ferrierite-H can be used as a catalyst in the chemical industry for the acid-catalyzed skeletal isomerization of n-butenes to isobutene, the raw material for production of methyl tert-butyl ether (MTBE).