MINERALOGICAL JOURNAL, VOL. 6, No. 5, pp. 343-364, SEPT., 1971

NEW OCCURRENCE OF FERRIERITE

SUMISAKU YAJIMA and TADAHARU NAKAMURA

Institute of Earth Science, School of Education,

Waseda University, Shinjuku, Tokyo, Japan

and

Eiji ISHII

School of Social Science, Waseda University, Shinjuku, Tokyo, Japan

ABSTRACT

Ferrierite is a very rare of the group. It was named and described in 191.8 by Graham. A zeolite was collected at the Itomuka mine in Hokkaido, Japan, in 1953. A preliminary investigation revealed that this mineral was ferrierite. Ferrierite from this locality occurs mainly as spherical aggregates of radiating blades and as interstitial fillings in propylite. This ferrierite is found in association with calcite, barite, pyrite and especially closely connected with heulandite. It is white in color, with a vitreous luster, and up to 0.5 mm in length. The first identification of this ferrierite was made by the X-ray powder method. Its Chemical com- position was close to the result of Graham's analysis, though ours was poorer in Mg than Graham's. The chemical formula will be best represented by

(Na1.32K1.57)Mg1.09 (Si 30.95 Al 5.03•@Fe 0.01) 35.99 O72.01. 18.82H2O. The indices of refrac- tion measured are a=1.483 9=1.484 1=1.486 and the specific gravity is 2.06.

Thermal properties of this ferrierite were studied by means of the deriva- tograph. Its DTA curve showed a large endothermic peak between 250•Ž and 260•Ž. A DTG curve revealed that its dehydration rate reaches a maximum of 0.85mg/min. at 260•Ž.

Introduction

Ferrierite was described by Graham in 1918 and named in honour of the late W. F. Ferrier of the Canadian Geological Survey. The 344 New Occurrence of Ferrierite

locality from which ferrierite has been reported is on the north shore of Kamloops Lake in British Columbia where it occurred as spherical aggregates of radiating blades enclosed in chalcedony. This chalcedony fills seams in flows in the Kamloops Volcanic Group of the Lower Miocene age (Graham, 1918). The sample for the present investigation was collected in 1953 by one of the present writers (Ishii), during his study of the mercury deposits in the Itomuka mine, Hokkaido, Japan. In the previous paper by Ishii (1956), the sample was considered to be ferrierite on the basis of its X-ray powder pattern and chemical analysis. However, the sample was too small in quantity to obtain accurate data. Some other localities of ferrierite have since been described (Baric, 1965; Alietti, Passaglia & Scaini, 1967; Wise, Nokleberg & Kokinos, 1969; Hayakawa & Suzuki, 1970), and some recent publica- tions have been concerned with the crystal structure of ferrierite (Staples, 1955; Vaughan, 1966; Kerr, 1966) and the preparation and

Fig. 1. Map showing the location of the Itomuka mine in Hokkaido . S. YAJIMA,T. NAKAMURAand E. IsIIII 345 properties of synthetic materials (Barrer & Marshall, 1965). Fortunately, we have lately obtained many additional samples from the Itomuka mine and carried out the present study with the purpose to describe the general features of its occurrence in the Itomuka mine and to present its mineralogical data.

Fig. 2. Geological map of the Itomuka mine 1. Andesite 2. Agglomerate 3. Rhyolitic welded tuff 4. Propylite 5. More altered propylite 6. Alternation of sandstone, conglomerate and mudstone 7. Alternation of slate and sandstone (Hitaka series) 8. Tunnel 9. River 10. Road 346 New Occurrence of Ferrierite

Mode of Occurrence The Itomuka mine is situated in the central part of Hokkaido, Japan (Fig. 1). The mine has been one of the greatest mercury producers in Japan. The base stratum of the mining district is 2 pre-Cretaceous bed (so-called Hitaka series) which consists of alterna- tibns of slate and sandstone bearing conglomerate and contacts neogene-Tertiary bed either by unconformity or by fault. The

Fig. 3. Structure of the Yamato deposit in the Itomuka

mine and the locations of ferrierite .

‡@ No. 1 vein ‡A No. 2 vein ‡B No . 3 vein, No. 3 lower vein ‡C No. 4 vein ‡D No. 5 upper vein , No. 5 lower vein ‡E No . 6 vein ‡F New upper vein, new lower vein ‡G No . 7 vein S. YAJIMA,T. NAKAMURAand E. ISHII 347 neogene-Tertiary (so-called green tuff facies) bed consists of pro- pylite (Miocene), and rhyolitic welded tuff, andesite, and agglomerate (Pliocene) (Fig. 2). The ore deposit is a vein-type deposit filled up the fissure or the fault zones in propylite (Fig. 5). Ore are metallic mercury and cinnabar. The produc- tive ratio of metallic mercury to cinnabar is seven to three being remarkably high. Gangue minerals are mainly marcasite, pyrite, quartz, calcite, dolomite, kaolinite and montmorillonite. Ferrierite was first found in a sample from the 3rd adit level in the Yamato deposit (1,030 m above sea-level) (Fig. 3). This sam- ple was used for the preliminary study. Afterwards, ferrierite has been collected from No. 7 vein on the 5th adit level and Nakano- sawa adit level (Fig. 4). These locations in the mine are in similar geologic settings and near the ore veins. Ferrierite occurs as interstitial fillings in propylite and as sphe- rical aggregates of radiating blades in druses. The aggregates are about 2mm to 5mm in diameier (Fig. 9). This ferrierite is asso- ciated with pyrite, calcite, barite and heulandite (Figs. 6, 7, 8, 10 and

Fig. 4. Sketch of a crack in the south side wall rock near 690m from the Nakano-sawa adit level. 1. Montmorillonite and alunite 2. Quartz and opal 3. Ferrierite, opal and marcasite 4. Propylite 348 New Occurrence of Ferrierite

Fig. 5. Photomicrograph of a thin section of propylite, crossed nicols. P1=plagioclase, MF=pyroxene

Fig. 6. Photograph of a hand specimen of ferrierite (FE) and pyrite (Py). S. YAJIMA, T. NAKAMURA and E . Isriii 349

Fig. 7. Photograph of a hand specimen of ferrierite (FE) and calcite (Ca).

Fig. 8. Photomicrograph of a thin section of ferrierite (FE) and barite (Ba), one nicol. 350 New Occurrence of Ferrierite

Fig. 9. Photograph of a hand specimen of ferrierite (FE).

Fig. 10. Photograph of a hand specimen of ferrierite (FE) and heulandite (He). S. YAJIMA, T. NAKAMURA and E. ISHII 351

Fig. 11. Photograph of a hand specimen of heulandite. b (010), c (001), t (201), m (110), and s (201).

Fig. 12. Photomicrograph of a thin section of ferrierite (FE) and heulandite (He), crossed nicols. 352 New Occurrence of Ferrierite

Eig. 13. Photomicrograph of a thin section of ferrierite (FE) and heulandite (He), one nicol.

11), which have been identified by microscopic observations and X-ray powder diffraction patterns. The ferrierite is especially closely connected with heulandite (Figs. 12 and 13).

Physical and Optical Properties

This specimen of ferrierite is white in color with a vitreous luster and consists of aggregates of blade-like grains. The mineral is soft and its hardness cannot be measured accurately. The spe- cific gravity is 2.06 as determined by a pycnometer. Staples (1955) determined the specific gravity to be 2.15, Vaughan (1966) computed

Table 1. Refractive indices of ferrierite S. YAJIMA, T. NAKAMURA and E. ISHII 353

2.11 and Aliett et al. (1967) calculated 2.18.

Ferrierite shows parallel extinction and positive elongation. The indices of refraction were determined by the dispersion method, with the results in a fairly good agreement with the previous data as given in Table 1.

Thermal Properties

Zeolites have the characteristic water of crystallization which is known as "zeolitic water". The dehydration tests of the speci-

mens free from impurities have been carried out several times.

Thermal properties of the ferrierite were determined by means of the derivatograph which was used for running thermogravimetry

(TG), derivative thermogravimetry (DTG) and differential thermal analysis (DTA) simultaneously, and under the following conditions:

TG sensitivity, 100 mg in full scale; DTG sensitivity, 10 mg per minute in full scale; DTA sensitivity, 100ƒÊV in full scale; heating

rate, 5°C per minute; chart speed, 120 mm per hour; temperature indicating thermocouple, Pt-Pt• Rh(13%) ; differential thermocouple,

Pt-Pt• Rh(13%)-Pt; sample weight, 343.5 mg.

The dehydration of ferrierite started at 50°C and continued to

600°C. There was a continuous slow loss in weight below 600•Ž,

amounting to about 12% H2O, which agrees closely with the water

determination in the chemical analysis. A DTG curve revealed that

the dehydration rate of the ferrierite reaches a maximum of 0.85

mg/min at 260•Ž. This DTG peak corresponds to the endothermic

peak in the DTA curve (Fig. 14).

On the basis of the features of DTG curves, have been

divided into four groups as follows (Imai, Otsuka & Yoshimura,

1964):

Group A: Minerals belonging to this group have only a broad

peak indicating the gradual and continuous dehydration. These

minerals include mordenite, chabazite and analcite. 354 New Occurrence of Ferrierite

Fig. 14. Thermographs of ferrierite.

Group B: Minerals belonging to this group are characterized by a very sharp peak, revealing their dehydration proceeds very rapidly in a narrow temperature range. Natrolite belongs to this group. Group C: Minerals belonging to this group have two or three steps and give a slow and gradual dehydration in each step. Heu- landite, laumontite and yugawaralite are found in this group. Group D: Stilbite, phillipsite, faujasite and thomsonite are not classified into any of the group mentioned above with respect to their DTG curves. Ferrierite belongs to group A. S. YAJIMA,T. NAKAMURAand E. IsHII 3.55

X-ray Diffraction Data The X-ray diffraction powder method was applied to the speci- mens with the aid of the Geigerflex (Operating conditions: X-ray spectrometer, Geigerflex Rigaku Denki Co.; X-rays, nickel-filtered copper radiation ; voltage, 30 kV; current, 15 mA; scanning speed, 1'/min; chart speed, 1 cm/min). The samples of ferrierite from several spots in the Itomuka mine and from Kamloops Lake. The X-ray powder diffraction data for the Itomuka ferrierite are very similar to the previous data as shown in Table 2. The diagnostic peaks on the powder patterns of ferrierite are 9.6A(200)

, 3.99A (321), (031), and 3.54A (112), (040). But the Agoura -and Sonora Pass ferrierites have been reported to show some changes

in certain peak intensities, especially (420), (330), (510) and (040)

(Wise et al., 1969).

Chemical Properties and Compositions

According to the reaction with hydrochloric acid, zeolites have

been divided into three groups:

1. Gelatinized in HCl (laumontite, natrolite, etc.)

2. Alter in HCl to hydrous silica (heulandite, stilbite, etc.)

3. Insoluble by HCl (mordenite, etc.)

Ferrierite belongs to the last group.

For the sampling, an experiment was designed to study the

relation between ferrierite and heulandite by means of qualitative

electron probe microanalysis (EPMA). The method of preparation

of the specimen consisted of resin processing, polishing and carbon

coating. The operating condition of the electron probe were as

follows: electron probe X-ray microanalyzer, Akasi TRA-25A; Ac-

celerating voltage, 30kV; probe current, 0.04ƒÊA; spot diameter, about

,0 .5ƒÊ; analysing crystal, mica, PET; counter, proportional counter

PR gas; full scale, 200cps; Time constant, 1 sec. The X-ray images 356 New Occurrence of Ferrierite

Table 2. X-ray powder data of Ferrierite

1. Itomuka, Hokkaido, Japan (present study) . 2. Kamloops Lake, British Columbia, Canada (Staples , 1955). 3. Agoura, California, U. S. A (Wise et al ., 1969). 4. Sonora Pass, California, U. S. A (Wise et al ., 1.969). 5. Tadami-machi, Fukushima Pref . Japan (Hayakawa et al ., 1970). S. YAJIMA, T. NAKAMURA and E. ISHI 357 of the specimen are shown in Plates 1 and 2. No particular concention is recognized of Si and K both in fer- rierite and in heulandite. Ca and Al differ from each other in the mode of distribution in the specimen. Ca is clearly concentrated in heulandite. Mg was below the sensitivity of the EPMA. Spot analysis was also applied to each mineral with the result that no Ca spectrum was detected from ferrierite (Fig. 15). For these experiments, the samples were separated carefully

Fig. 15. X-ray spectra obtained by the spot analysia of ferrierite and heulandite.

The results revealed that there is no Ca spectrum in ferrierite. 358 New Occurrence of Ferrierite Fig. 16. Spectrochemical analysis of ferrierite and h eulandite. S. YAJIMA,T. NAKAMURAand E. ISHII 359 from heulandite and other minerals, and checked by the spectro- graph operated under conditions: spectrograph, Shimadzu U8-1; slit width, 2/100mm; gap, 3mm; electrode, National carbon special; sample hole, 0=2mm, D=5mm; exciting method, AC arc; exposure, 30 sec ; current, 5 A; plate, Fuji process; development, D-19, 19.5°C, 3 min. Essential elements of ferrierite detected by the spectrochemical analysis were Si, Al, Na, K, Mg and Fe and trace elements were Ca, Ti and Mn (Fig. 16).

Chemical formulae of ferrierite

(Na 1.32K 1.57)Mg1.09 (Si30.9 A15.03 Fe0.01):35.99 O72.01-18.82H2O(Present authors) (Na, K)4 Mg2 (Si30A16) O72(OH) 2. 18H2O (Staple, 1955) Na1.5Mg2Si30.5 A15.5 O72.18H2O(Vaughan, 1966) K0.51Na0.25 Ca0.99 Mg2.98 (Fe1.20 A17.25 Si27.50) O72.2312H2O (Alietti, 1967) Na1.8K1.4Mg0.6 (Si31.6 Al4.4) O72.18H2O (Wise et al., 1969) 360 New Occurrence of Ferrierite

An ordinary chemical analysis was carried out as follows: Mag nesium oxide was determined by the gravimetric methed (Mg2P2O7) and by the chelatometric titration (ethylene-diamino-tetra-acetic acid) because ferrierite contains magnesium oxide. Both results agree very well with each other. Potassium oxide and oxide were determined by the flame spectrophotometric method. The water content was examined by the Penfield method. The other elements were determined according to the usual methods. The result is shown in Table 3. As will be noted in the Table, the sum of Si+Al is near 36 and O/(Si+A1) is close to 2, the values characteristic of the zeolites . The chemical formula of this ferrierite shows some differences in the values of alkali and magnesium as compared with the published analyses, and it is poorer in Mg in comparison with Graham's result of the Kamloops Lake sample.

Acknowledgements

Dr. Kitaro Hayase contributed a great deal to the present study . Dr. Kin-ichi Sakurai and Dr. Akira Kato, the National Science Museum, Tokyo, who kindly supplied the specimen of ferrierite from Kamloops Lake, Canada, and gave many valuable suggestions . The writers express their appreciation to members of the Nomu- ra Mining Company who gave many additional samples . Mr. Atumu Tunashima, Waseda University, kindly carried out the thermal analysis of ferrierite.

REFERENCES

ALIETTI, A., PASSAGLIA,E. & SCAINI, G. (1967). Amer. Min., 52, 1962. B ARK, L1. (1965). Bull. Sci. Conseil Acad. RSF. Yougoslavie 10 (6) 177 (Geg). Abstract in Chem. Abst. (1966) 65, 16690. BARKER,R. M. & MARSHALL,D. J. (1965). Amer. Min., 52, 484. G RAHAM,R.P.D. (1918). Roy. Soc . Canada Proc. & Trans ., 3rd Ser, 12. S. YAJIMIA, T. NAKAMURA and E. ISHII 361

Sect. IV, 185. HAYAKAWA, N. & SuzUKI, S. (1970). "Min. Geol". Journ. Soc. Mining Geol. Jap., 20, 295 (in Japanese). HAYASE, K. & ISHII, E. (1954). Rep. Min. & Metal. Inst. Jap., 80 (in Japa nese). IMIAI, N., OTSUKA, R. & YOSIIIMURA, N. (1964). Memo. Sch'l. Soc. & Eng., Waseda Univ., 28, 1. ISHII, E. (1953). Synopses Eng. Grad. Sch'l. Sci. & Eng., Waseda Univ., 2, 95 (in Japanese). ISHII, E. (1956). Gakuin Kenkyu Nenshi, High Sch'l. Waseda Univ., 1, 103 (in Japanese). STAPLES, L. W. (1955). Amer. Min., 40, 1095. VAUGHAN, ?.A. (1966). Acta. Cryst., 21, 983. WISE, W. S., NoKLEBERG, W. J. & KOKINOS, M. (1969). Amer. Min., 54, 887. WINCHELL, A.N. & WINCHELL, H. (1351). Elements of Optical Mineralogy, Part II. John Wiley, New York. 337. YAJIyIA, S. (1.958). Mercury Mining in Japan and Outline of Nomura Mining Co., Ltd. Nomura Mining Co., Ltd. Tokyo Japan. YAJIMIA, S., ISIHI, E. & NAKAMURA, T. (1963). Geol. Soc. Jap., 74, 132 (in Japanese).

Manuscript received 5 July 1971. 362 New Occurrence of Ferrierite

Plate 1. X-ray images of ferrierite and heulandite. 1. Back scattered electron image. 2. Absorbed electron image. 3. Sketch of the optical image of the field corresponding land 2. 4. Back scattered electron image of ferrierite. 5. Absorbed electron image of ferrierite. S. YAJIMA, T. NAKAMURA and E . IsHII 363 364 New Occurrence of Ferrierite

Plate 2. X-ray images of ferrierite and heulandite. 1. Back scattered electron image. 2. Absorbed electron image. 3. Characteristic X-ray image by SiKa radiation. 4. Characteristic X-ray image by CaKa radiation. 5. Characteristic X-ray image by KKa radiation. There is no signi ficant image contrast in 3 and 5, indicating the homogeneous dis, tribution of Si and K in both minerals. 6. Characteristic X-ray image by AIKa radiation. This shows that heulandite contains more Al than ferrierite.