Barium-Adularia from the Isagosawa Mine, Iwate Prefecture, Japan

九州大学学術情報リポジトリ Kyushu University Institutional Repository

Barium-adularia from the Isagosawa Mine, Iwate Prefecture, Japan

Yoshimura, Toyofumi Faculty of Sciences, Kyushu University

Shirozu, Haruo Faculty of Sciences, Kyushu University

Kimura, Morihiro Faculty of Sciences, Tokyo University

https://doi.org/10.5109/1524113

出版情報：九州大學理學部紀要 : Series D, Geology. 4 (2), pp.163-166, 1954-07-31. 九州大学理学部バージョン：権利関係： Mem．， Fac． Sci． Kyushu Univ．， Ser． D， Geology， Vol． IV， No．2， pp．163－165，

text・fig．1， tables 1，2， July，1954．

Barium・adularia from the Isagosawa Mine， Iwate Prefecture， Japan

Toyofumi YOSmMURA， Haruo SHIROZU and Morihiro KIMURA

White veinlets traversing through the hematite ore of the Isagosawa mine were fomd to be composed almost monomineralically of crystals of barium・adularia， which had been analysed by H． SHIRoRu with the fo110wing results（table 1）．

Table 1． Chemical composition of barium・adularia

wt．％ mo1．％ SiO2 61．12 0r 88．6 A1203 20．58 Cn 6．6 Fe203 0．29 Ab 4．O CaO ／ 0．16 An O．8 MgO none BaO 3．36 K20 13．87 Na20 0．41 1gl． 0．30

100．12

The crystalline aggregate of barium・adularia looks quite similar to calcite， show・ ing distinct cleavage faces． It is not transparent， colour white with various shades

of reddish brown． Under the microscope it shows rhombic boundary， characteristic to adularia． Between the crossed nicols we can see mottled extinction of light and an abnormal interference colour， slight indigo・gray．

Specific gravity； d▲1°＝2．585

Refractive indices； α＝1．520－1．522

ッ＝＝1．526－1．528

（一）2V＝75°

An X・ray powder photograph of the barium・adularia con6rms its identi丘cation （text・69．1， no．1and table 2， no．1）． It was made in 5．73 cm radius camera with Cu・Kαradiation． A powder pattern of adularia from the Obira mine is compared in text・丘g．1， no．2and table 2， no．2． A Iittle difference between them suggests the smaller size of the crystal Iattice of barium・adularia． The authors wish to thank 164 T．Yoshimura， H． Shirozu and M． Kimura

Tab．2． X－ray powder diffraction data for barium・adularia and adularia

「 ‘No．1 No．2 i No．1 No．2 ：Barium．adularia Adularia Barium・adularia iAdularia lISagOSaWa mine Obira mine Isagosawa mine ．Obira mine （Cont，d）i （cont／d） 1 d（A） 1 1 d（A）む 1 d（A）む 1 d（A）む 596733106114507925 W 6．60 M 65544333333322222222222222111臼 1．428 VW 5．90 W 94 M 1．409 WW 1．407 漂WWS鴨品SS晶晋M鴨s鴨輪SSS需WWWWWWSSWMMSW飢器8050塁且009178器494239田2923認㎝㎝9793額W 1．385 W 1．381 4．64 W 64 W （Q）1．372 4．25 VW 1．365 3．95 …W 1．340 ▽WWM溜認WWW溜W 1．340 3．78 W 1．328 3．49 iBW 1．310 1．314 3．34 ，W 1．289 1．289 3．25 …W 1．278 1．278 3ユ4 lw 1．261 1．258 3．005 IVW 1．227 1．228 2．919 iVW 1．210 1217 2．778 ‘W 1．197 1．197 2．590 VW 1．181 1．182 VW 1．158 1．157 ー W 1．147 1．148 W 222 2222211111111 工⑫器≡題。6㎝塁聖8。7霧㌘101 5905758162613 9VW 1．127 1ユ24 W VW 1．111 1．109 W VW 1．099 1．097 VW 1．084 1．084 VW 1．0540 WSMWMMMMW潟WW lVW 1．0348 lVW 1．0268 VW 1．0145 VW 0．9911 VW 0．9822 VW 0．9702 VW 09709 VW 0．9626 一 VW 0．9455 VW 0．9444 i品 1111111111111111877776665555544407520853964107536946324349150826VW 0．9291 VW 0．9174 lVW 0．8986 0．8917 0．8903 畷 l VW VW v溜 VW 0．8828 VW 0．8807 W VW 0．8740 一 VW 0．8672 BVW 0．8668 W 11111111163 342688840lW VW 0，8548 iBVW 0．8552 W 弱認弘47麗認．VW 0．8412 VW 0．8415 W VW 0．8299 W 0．8305 W lv鵠ドー， WSW離 lvも …珊

1 Cu－Kαradiation Camera radius｝ γ＝5．73cm VS： very strong the both edges S： strong of broad line M： medium W： weak VW： very weak B： broad line Q： quartz Barium・adularia from the Isagosawa Mine， Iwate Prefecture， Japan 165

Mr． M． MIYAHIsA for providing the specimens of adularia from the Obira mine used in this work．

Text・6g．1． X・ray powder di任raction photographs of barium・adularia and adularia．

No．1． Barium・adularia， Isagosawa mine．

No．2． Adularia， Obira mine．

Baritlm．containing feldspars were reported in 1940 by T． YosHIMuRA苦from the manganese deposits of the Kaso mine， Tochigi Pref． Japan． The iron ores of the Isagosawa mine do not contain much manganese， especially those of the higher iron・ colltent showing the less manganese． But they occur as lense・shaped metasomatic ore bodies in a diabasic dyke which traverses the strata of the Paleozoic formation， and s㏄mingly related genetica11y to manganese deposits which are found in the Paleozoic region of this country．

＊ T．YosHIMuRA：Sヒudies on the minerals from the manganese deposit of the I（aso mine， Japan；Jour． Fac． Sci． Hokkaido Imperial University， Ser． IV， Vo1． IV，313－451（1939）．