Chemical Composition of Ferrierite WILLIAM S. WISE 93/06
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American Mineralogist, Volume 61, pa ges 60-66, 1976 Chemical composition of ferrierite WILLIAM S. WISE Department of Geological Sciences, University of California Santa Barbara, California 93/06 AND R. W. TSCHERNICH 532 Avenue A, Snohomish, Washington 98920 Abstract Ferrierite specimens from localities at Altoona, Washington; Silver Mountain, Alpine County, California; and Pinaus Lake, Monte Lake, and Francois Lake, British Columbia, have been analyzed by microprobe methods. These new analyses are combined with available data to delineate the compositional range for this zeolite. The frame work composition ranges from (Al7•5Si27 5072) to (Al,Sia,072). The a cell dimension varies linearly with the Si content. There are between 3 and 5 exchangeable cations (univalent and divalent) per unit cell of 72 oxygens, but with wide variations; the amount of univale11t ions ranges from 21 to 85 percent. There is no clear parititioning of the univalent ions, as the Na/(Na+K) ratio is highly variable. Mg is clearly fractionated in all ferrierites (Ca/(Ca + Mg) < 0.40), regardless of the amount of divalent ions. The highest known amounts of BaO (2.54%) and SrO (0.40%) are in the Silver Mountain ferrierite. Associated zeolites commonly include clinoptilolite or heulandite, although mordenite and dachiardite also occur with ferrierite at Altoona. The broad compositional range of ferrierite indicates that it can crystallize from solutions with a wide variety of alkali and alkaline earth cations, none of which are essential to the zeolite. If present, Mg ions are fractionated into the zeolite. Ferrierite crystallizes in response to high silica activities. However, to account for the range in silica contents, the a810, must be coupled with other variables, such as temperature or aH,o, in order to prevent crystallization of other high silica zeolites. Introduction Ferrierite from five more localities in the western There have been few published analyses of the United States and Canada has now been collected zeolite ferrierite, even though it is now known to be and analyzed. The purpose of this paper is to present more common than once believed, occurring both as this new analytical data, which illustrates a broad a cavity-filling material in basaltic rocks and as a range of compositional variation, and to show the diagenetic mineral in rhyolite tuffaceous sediments. chemical relationships with closely associated zeo Following the original description of ferrierite from lites. Kamloops Lake, British Columbia, by Graham Ferrierite is a silica-rich zeolite, forming thin, (1918), it was not until 1967 that another occurrence bladed crystals of orthorhombic symmetry. The crys was discovered and described by Alietta, Passaglia, tal structure, determined by Vaughan (1966), is char and Scaini (1967). Then ferrierite was analyzed and acterized by (Si,Al)04 tetrahedra forming five-mem described from two localities in California (Wise, ber rings linked in complex chains parallel to the Nokleberg, and Kokinos, 1969), one in Japan (Ya orthorhombic c axis. Between the chains in each unit jima, Nakamura, and Ishii, 1971 ), and Austria (Zirkl, cell are two large cation cages, which contain hy 1973 ). Regis (1970) reported the existence and com drated cations, commonly MgH, and two channels, position of ferrierite forming extensive beds in central containing the loosely bound and highly disordered Nevada. remaining cations and water molecules. 60 CHEMICAL COMPOSITION OF FERRIERITE 61 Sample locations southeastern Kamloops District, British Columbia, Altoona, Washington in basalt flows belonging to the middle Tertiary Kam Ferrierite occurs in the Miocene Columbia River loops Group (see Jones, 1959). The ferrierite occurs basalts near Altoona in western Wahkiakum County, lining vesicles and in calcite-filled nodules in a fine southwestern Washington. The zeolite-bearing rock grained, greenish-black basalt composed of micro originally came from a small quarry near the east end phenocrysts of labradorite and augite set in an of the settlement of Altoona, but most of the speci opaque glass matrix in a large roadcut east of Monte mens were collected from riprap along the Columbia Lake and along railway cuts one mile south of the River in Altoona and an area about one mile west of lake. Ferrierite also occurs in basalts, exposed by the town. logging roads south of Monte Lake. The ferrierite occurs as linings and radial groups of The ferrierite occurs as colorless to salmon-col white or colorless blades in small vesicles and open ored, thin blades which range from 5 to 15 mm long. spaces between fragments of brecciated basalt. The In the past this material has been mis-identified as basalt consists of abundant glass with less than 20 either mordenite or mesolite, probably because of the percent plagioclase and clinopyroxene. Some frag thinness of the crystals. Other minerals include anal ments contain vesicles (1 em) commonly lined with cime, chabazite, heulandite, levyne, stilbite, and siderite and covered with greenish-black nontronitic thomsonite. clay. Pinaus Lake, British Columbia The habit and forms of the ferrierite are nearly identical with that from Agoura in the Santa Monica Ferrierite has recently been found in altered basalts Mountains, California (Wise et al, 1969). In both of the Kamloops Group along the shore of Pinaus areas crystals display a dominant (010) face, while Lake, 8 miles southeast of W estwold, British Colum those from British Columbia have a dominant (100) bia (see Jones, 1969). This occurrence is similar to the face. Closely associated with ferrierite at Altoona Kamloops Lake location, in that the ferrierite is is Ca-clinoptilolite, dachiardite, mordenite, chal found as cavity linings of calcite-filled nodules. The cedony, and calcite-all have grown on the side crystals are short, red to white blades, which are rite and clay lining. A common sequence of commonly arranged in orderly rows of crystals cross crystallization is siderite, clay, mordenite, ferrierite, ing each ball of crystals. and Ca-clinoptilolite, followed by dachiardite. A de tailed description of these minerals is in preparation. Francois Lake, British Columbia The late R. M. Thomson found ferrierite as minute Kamloops Lake, British Columbia needles on collinsite and carbonate-fluorapatite at The type area for ferrierite, first described by Gra Francois Lake, over 300 miles northwest of Kam ham (1918), is in a cut along the Canadian Northern loops Lake. In the same rocks, ferrierite is also found Railway on the north shore of Kamloops Lake, east apart from the phosphates in breccia cavities and of Kamloops, southern British Columbia. Even vesicles of the brown, aphyric andesitic rocks of Ter though this ferrierite has been adequately described, tiary age in that area. This latter ferrierite occurs as it was recollected along with the associated small (2 mm) colorless blades and radial groups asso clinoptilolite for more complete analysis. The zeolites ciated with 1 mm crystals of brownish heulandite. occur in a deeply weathered, porphyritic olivine-ba salt flow-breccia in the Kamloops Group of middle Silver Mountain, California Tertiary age (Cockfield, 1947). In altered andesite near the old townsite of Silver Ferrierite has formed in seams and vesicles in the Mountain, southwest of Markleeville in Alpine flow-breccia. Within them calcite and chalcedony County, California, ferrierite occurs as very thin, may cover the earlier-formed ferrierite. Pale brown white to orange blades. These commonly form mats ish-red clinoptilolite is sparsely associated with the of crystals but also combine to form compact balls ferrierite, which occurs as colorless to red stained and short rows of oriented crystals, similar to that blades, forming linings and radiating balls up to 15 found at Pinaus Lake, British Columbia. Ferrierite is mm in diameter. associated with sparse heulandite and barite. Monte Lake, British Columbia Rodope Mountains, Bulgaria Ferrierite has been found near Monte Lake, about A container of ferrierite crystals labelled "Rodope 6 miles west of Westwold along Highway 97W, Mountains, Bulgaria," was included in a suite of 62 W. S. WISE AND R. W. TSCHERNICH zeolite specimens sent to us from Drs. Golubova and crometers in thickness. Therefore, whole clusters Belitsky of the Siberian Branch of the Academy of were embedded in epoxy, and ground until the center Sciences of the U.S.S.R. of the cluster was exposed. The mount was then polished and coated with 250 A of carbon. The analy Electron microprobe and X-ray data ses were made on an ARL electron microprobe, using All of the ferrierite samples analyzed here are clus an accelerating voltage of 15 kilovolts for all elements ters of very small blades; some are less than lO mi- with a sample current of lO nanoamps. Standards TABLE I. Analyses of Ferrierites l 2 3 4 5 6 7 8 9 Locality Altoonat Altoonat Sta. Monica Kamloops Pinaus Francois Monte Lake Silver Mtn. Rodope Mtns. Wash. Wash. Mtns., Cal. Lake, B.C. Lake, B.C. Lake, B.C. B.C. Cal. Bulgaria n* 2 2 8 6 2 2 3 Si0 71.50 72.18 73.07 70.14 67.79 66.11 66.33 65.02 70.00 2 Al 0 10.18 10.87 10.00 11.45 11.00 13.20 13.18 13.19 11.31 2 3 Fe o 0.01 0.05 0.02 0.13 1.57 0.30 0.27 0.12 (0.30) 2 3 MgO 0. 59 1. 52 1.19 2.56 3.23 3.34 3.41 3.00 2.15 CaO 0.11 0.97 0.30 0.15 0.51 1.02 l. 39 1. 05 1.62 SrO 0.13 o.o 0.0 0.18 0.0 o.o 0.34 0.40 o.n BaO 0.13 0.38 0.09 0.38 0.88 1.97 0.41 2.54 0.25 3.64 1.