<=> J. Hot Spring Sci. /3 22ῌ30 ,**3ῌ῎ : 

z{|}+ ~, , ,+

0  ,+

3

1

+1



Chemical Consideration on the Formation of
Yunohana Sinter at the Myoban Area,
Beppu Hot Springs
Masami ICHIKUNI+, Nobuhiro KATO, and Daijiro OTANI,

Abstract
An evaporate-like precipitate containing halotrichite and/or alunogen, named Yunohana or sinter for its use as bath additive, is produced in a thatched cottage at the
Myoban area, Beppu Hot Springs, by a traditional technique, which consists of percolation of H,S-containing fumarolic gases through blue clay bed and evaporative crystallization from resulting solution on the surface of the clay bed.
In this process, H,S is oxidized to H,SO., which extracts aluminum and iron from clay
minerals. Blue clay, composed mainly of smectite and kaolinite, is also characterized by
the presence of ﬁne-grained pyrite. Pyrite is oxidatively-decomposed to give H,SO. and
FeSO.. Chemical behavior of iron through the formation of Yunohana depends on its
oxidation state : Divalent iron forms halotrichite with Al, (SO.)-, while trivalent iron independent ferric minerals, thus resulting in red-colored Yunohana. To produce Yunohana with a high yield, supply of blue clay rich in divalent iron is essential. The additionof trivalent iron to blue clay was found to be ine#ective in promoting halotrichite formation.
Key words : Beppu Hot Springs, sinter, halotrichite, alunogen, blue clay῏

῍?@<=ABC DEFGHIJKDLMNOPQRSTUVWXGFQYZ[\]^_3`a_ bcd6efghiQjklmnopZqrTsQ LMtZuvwxyHIJKt+  ,.+ῌ*2*+  !"# +ῌ1ῌ/*. + Professor Emeritus atTokyo Institute of Technology, (Contact address) +ῌ1ῌ/*. Wakabadai, Asahi-ku, Yokohama ,.+ῌ
*2*+, Japan.
,$%&'(')*+,-'./01 $%&'23'*+,-456*+6789 ,--ῌ***- :; :; ,ῌ-ῌ+, , Wamiles Cosmetics Inc., Wamiles Holistic Beauty Research Center, ,ῌ-ῌ+,Konan, Konan-ku, Yokohama ,--ῌ***-, Japan.

88

/3  ,**3

:    !"#$%&' ()* +!  +,-.!
/! 012345
6 789:56; <=)> 58?0123456@ABCD<
=AE;FG Fe, 0 Al, SO.- HIJKL69756(M Fe- 0
IN  ῍ = (! 
O!(PQNQ0 Fe ῌ "* R
#STUVWXWY :   KL69756 "#ZW[? +     $\%


U &]

<_ (`_Ca) U  0'AE/IN#b*0cdef<=()*UgJ  +h(HiJ,E-^/ ;l0 MEJf 


0

^

U jgJk.

 01DmC; Unop@no 2(3q.QJrDgNs tAE+h(45!

67 no ou08v9fJUB pgJno:; <w<
=INxyz{Jf +h0 >  '>)>Jf 20(?|I  ῌ "#$%&' )' }(

UgJ ~?=!

0KL69756 Al,Fe SO..ῌ,,H,O "#ZW[?

Al, SO.-ῌnH,O n+0+2 U(l*@ANgJ
DUB lAl.<  SAU 

BC<0 + mmῌday(E gJ/!  6F0G ;HIf;  ,**0 I0 JKLMN ON  ,**1 0

67 10NCP(QHIJIN

0~IJ +30* I)N ;CRD STUJf NM@ fJ;JC

Cf  NQb* 
f   Y 0  / ῌ= / MVWa pXIJfAM|JfC

 Z¡[(;  NQ \] ¢£ ¤¥(V!U,  / IJ0^E +300 p?W ¦A §¨ +30/ ©IN_?ª« ¬p;  _?ª=­ _?ª® ; +31* ¯N; U E(Table + °! `± NQ Lovas +320 VIN²< PfKL69756 ?a;b

IN C0©ICAgN ,**1 p. +,* ; - W ?aOPJf²cCKL69756 ?a . `±IN +  , 0EA H,O kU
0¢* -d³´ µfp;  -  . e-U fI +  , 0
ED +** [¶-dIN; U·  NQ¤¸' l;¹Jf U  ¤¥ +  , 0 H,O º»? ae-¢*pB; ,/῍ ¦a_DCgJf Locke E,**1 0¼gpKL69756 h'k.(I 1, > ¼g ,-..2῍ ;H,O ¹(°IN  ¤¥(fJ¹N H,O f!ij(?a +.
lk0ACB½l
89

XY- Z[\]- !^!_`8abTable + Chemical composition of Yunohana Sinter(Content given in ῌ. SFe/Al shows total Fe/Al in molar ratio. For theitems denoted by an asterisk, see footnote.)ΐ + ῒῌ῎ῌ῍῏ῑῐῌ 
SFeῌAl  Fe ῌ Fe ῍Al*   

Na,O
K,O
MgO
CaO
MnO
FeO
Fe,OAl,OSOH,O
Insol

+

,

-

.

*4-*
*4+*
*400
*4-,

*4*.
*4*.
*40+

*4*2
*4**4-.
*4+.

*4*/
*4*,
*4+-

*4,+
*
04.1*
+.4-1
/*4*,.4*1.4+1*.41,41+34+3
*
,24.+

*4,1

*4*/
34**
*4,,
+*40+
-/4-3
.-412

/41/
+41/
++4,--4*.04,2
+4-*

Total
SFe/Al  

3343-

334,/

*4.0

*40+

*4,3

+ : !"#$%&'()* +,- +30/  SO- ./0123) 2
45/6
, : !"789 !":$- +31*- p. ./1 () FeO *5
;- <= Fe >? Fe,O@ ABC.<)  S, SiO, 3)*GHInsol D  E F A 23)- : I. +300 () 5JKL ,**2 AMNOPQ;4<)
. : Lovas +320 ()RSTUVWT *c d;ef5RSTUVWT25ghiPjkAlm<) Table + 2c d

ng %&o(6pq4

SFeῌAl ef5RSTUVWTr) *./ (sAK4

X- z {|3) c d}c d ~c d 3)
 Fe ῍ G - Jw.gX
23y 2;$)
<)
}c

῍

/.

;.<) ~(<)A /- w  G῍OH ? SO. 24;4<)
d6 
Table ,</ e w< x25 /./)(y FehiPjk tuv)

~c
c

d

b

d ,**/ @)- w<<

+*ῌ 



*

c

23) w¢£d/.

¡4<A¤s23) 5Jc d¥¦ A §¨©w ª x¬ ­® Fe,´. 2A1 
2./ Fe

-

Fe-

;µ.< o !«5¶· Fe-¯°;¸

<2«)¯°±)23)  ²) «- ³¯°3) ~c d

¹º ,**1- p. /. ;}c d ~c d² »    AX¼)
OPQ ²½23);- ³´. Aef5RSTUVWT25 RSTUVWT90 /3 . ,**3

!

Table , Chemical analysis of +*῍ solutions ofwhite-colored and red-colored Yunohana
Sinter (Concentration given in mg/L) ,
 +*ῌ  mgῌL

Na
K
Mg,
Ca,
Mn,
Fe,
Fe-
Al-
F
Cl
SO.,
*

"#$%&'( : )*+,

/0  Fe, : Al- 12
3& 5 Al

-

#

+:,

+ : +.02 43&

6 3 Fe



,


+ : +.01

67839

 Al- :;<6=>?@A

?BC(:D:EF 78

White-colored
Yunohana

Red-colored
Yunohana

+*4/
00
,+
14.
/,**
-0**
.,**
-4/
++*
.+***

*43
*4/
11
.1
24.
/+**
.3**
.+**
-41
.2
.-****G ῌ HG ῍ HI E
JHKLM NO EBGPQR: 39 #  789SFe ῍ )M6%EF&TU

VUBW # 

E643& E&X SFeῌAl  12 =>?@A?'(# !

SFeῌAl Y5"Z

3 : [S Fe 678  # +300 \]ῌ ! ^#$3<_`$a'b%c'( ῌd2efghiHGj)*k    
 (B&;

E SFeῌAl 6 *  *./ l#5 P*#d2mno=>?@A?
LM   $apq#$3<r<=>?@A?6'(E6slt7#d2mnoB'9Y9# 5 uv#

d2mnow%#  Bx( : [S %c'( SFeῌAl  *./ yI5 c#z{<uv# * # 39 &Y9 |} ~#$3<| 6E # +300 
x(6II)*

E

3 F 3&'~#T#+,-"~,- 43&'~#T6{  G)Bi,- ] "~,- 6)<3 E<3  ,**1 p. 21 i6 E6:3,-B.: F SFeῌAl 6 *./ Y5"Z3&'(/ M 78 ῌ 0

FeSO.ῌ1H,O B(: 9  +30/ & X 

B3 r(6Gd2efghH 5

E#G ῌ H G ῍

6'9;<3 =>?@A?#3< 3
N(Y9# SFeῌAl 6 *./ # 3& ¡<E6=>?@A?
Br(: 3 &=>?@A? d2mno ¢-GP
1£ LM ¡< ¤2<¥¦ ¦  #G)§3#Y¡<iIE
P¢$): =>?@A?N¨P#3<©ª «¬64E
5(6­§3#®:«¬¯°± 33¡<Y3 ²³´µggh ²¶ ῌ
=>?@A?7 ῌ B8·<3+E<3 Locke et al., ,**1 Table ,  Y9#¸5(<¹º)j)69»E
E6­§3#®<¼^B 36 ½ 

91  - 
-+ 

  ,**1 p. +*,   ! "#$%&'($")*+$ ",-. /)01.2- 3214 567897:$;14<= 114'>: 178;? >8'@ ! /)0?.:AB 5 !"'#$/ %C1D?&E>:'()2 * 'F +,GH-"IJKL<M)28&'.'
)N+ 5&"/O01<28'2PQ'3BR+ +,6ST"45UV'W$XX<YQ UV678&'Z-$ "< +,ST/[9"\8]6.<3BR+$>8'28'2 ST^:(_B.;</28`"a<$6.,=-$ 6: * '=bcd<=-$.Q 66.,!
>e?f@"gh/,<=3A.>:Iijklmj nopLqJ.,'Br'C'Dst/uE<= !"<FA$ "A/mvJ Fe, Fe- Al- SO., "!GHX<
IJ/K7C<= AmvJ"wxDyLz{|.1}M'P-GHX<~E>: 56< .NE/$+'COP682s:282Q 1CO1<RSPQ'8:  1P]Y: D1T=?.U'2-  ,**1 p. ++*  C#"V7<2] %CO1"D '&E/.W ,X- !Y?2>e?"Z6., E"['/.2-  -,

6/17:"wX2 13ACO1<= 5:'<(\:>] (C:5:'< 1N]^8 +300 < O16'_:H`<=: 1"(C:-!"<(>:6.2]
$--78a noDE,6b26.'2 1O'c)AX:.) 5:'d->1, 78¡AX:.2s: FAef<)2
FA¢g"-( hAi("jk$£¤+30/'P. SO. wl¥0¦¢..,'m)'n ,/ op' 0.1+ῌ -2 op' 1.*2ῌ .2 /* o§'FP5 +*ῌ 'qrs¨H`'2.Q t©=|.2-$-ª> ,* cm<=-$ X$ ,**1 p. ++1  Au«¬ -* o0< .* mm ',­®6."v¯$
6:8°L±'%² * ³´78 -* opX<'FA$ SO. l"_µB SO. FAl-!"'wx>:$l.-!GH'NE$ 'wX:l"¶·$,'2 ·µ-!GH + cm, y$'NY2Q6.'/ X 
&H78-!z '¸{Hx + cm, m|7" 7xª> . cm <=6.78 . cm- -! 7xª>" ,* cm. ,* cm- .2}?Iijklmj}? +.3/ gῌcm-  +323 <¹º<)5Q<= 

'72»~¼/< 66<½Vs}?. + gῌ92



/3  ,**3
cm- 

  SO. 

'( )*+

. cm- 

!"#





:

 .-῍ $ .*῍ %&

SO. .cm-+gῌcm-*..*+.0g%,   ,* cm- 

SO.   &- , gῌcm- %  SO. .

/ 01234 0.2/῍ %&' )%567,*cm-,gῌcm-*.*02/,.1g)849:+ ..- g   )8 + ;<6=8> +.* mg %,  ?#@A 
B !" ? C(+DEF8%=8> ? #$,?" + ; 3- mg G 0/
mL %,  )8HI%+ *.-- L %=  &J '(B .* m, 5K8> + 5 +-* m-HIB)*F8 )%, 
 !"BHIC(++L ? F8 ,MN+-O !" ? . / R? STU!V&J PQ ,

W0XY= B ) Z . / %

O*1[,O

23, 4 N5\^$5K  )84 _`7 !"#
=4 +300 

67BK 8]9K )%B

Fe, Al- SO.,: ;a + : , : . 5K )%B<GO>? @bO+ !"# c A%= 

B

= B

de fg%%'V`h1iABjB= C*,; kl V`h1iAmB=%Cn+O  )8 DBV`opqC;'E5FF8 krDGOBs N5K  &J  Bt HI = )%') Juv+O 

Kw4D LMN*O 5 RDx ? C(+Pz+?D ῍ y

>?{| PzBQ,O%R,}~,3(B S= %@b

DmB57 T U(I V7/  ) V7/ ` A# Y

34WX+

9/5K* Kw4 !"C(+ Fe ῍ B Fe ῌ 

F8 )%bZB K,[N48,3( 4A, !"B\,3(N5K* ) 5]Fe ῍

9/Pz+' !"#

^_PQB,O)%`-ῌ- ῑ῔ΐ῍῎῏ῒῐabAc= d  BeIC fQ sg/5K  x/: fhC(+,; T2# c A%= ' %"@!Ax/c
A%= ' iAF8  "@!Ax/?]h T2# ]34V`"!]h5 5K )%34fhB O pH 8]¡(+O )%BA3 ¢j%,  c AT2# AV=4 +300 C(+£¡8

B AVBkl ¤#?¥AVmn¦+£¡8N / AV, G Fe ῌ% Fe ῍ 'F8+O,O 4 Fe  Fe,ODxBG8)%

5X' 5K* Rfb34§¨{j X o©pm5AVªq ῌ r«

+302 C(+43F8

 YBs¬t­ uv %®'w7+O  ) 
¯xῌ&° +3// C(+±I%+²³F8 ´ x/%+_A_!#µT2# %¶>8+O  B·[F8+O  )  X¸aAV5 /** y¹&

48 zaº1T L{/%+jB DC ' %| F8 )84 :  Table - X= »¼4 {j½O+'R Fe ῌAV£¡8+O,O93   Table - Chemical composition of blue clay
from the Myoban area and of blue-grayclay from Sounzan (Content given in
wt.῍)
 -


 ῍
Myoban area

SounzanSiO,
TiO,
Al,OFe,OFeO
MnO
MgO
CaO
Na,O
K,O
H,O ()H,O ()

/14,.
*42+
+0401
343.

tr
none
*4+*
*4*2
+-4-1
+4,-

.040/
*4,1
+24-,
1413
n.d.
*4*/
-4++
,4/2
*4/*
*4,/
0400
+-4/.

Total

334..

3341,

SFe/Al*

*4-2

*4,1

*

Fe

Al



&p 5q / Al

X/ Fe!"#$%&'()*+,./!"#$%&01 2+3)45 6 7

8 9:/-,;<2+= ,>?ῌ@> +3/.

Aῌ8

+302 /BCDEF*D5+ - AGH

I  JK+,

01LM%

N%&JK+ OP pH QRSJ4T Eh UIV
W /BCDXYF*+  Eh 9J
K*QUZ[\JXOJK+ ]^_` ,a;2+, pH,  Eh de9bc

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D5+ = Bq4

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,FeS,,H,O1O,  ,Fe,.H.SO.,!"#$%& U/B+  UI ),2+R+Jb45, = B
q/ , @, -,.2+= J&p/

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H,O 

I1 6I7h I18%^`

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JKC&p/© ,*D5+¨J

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Fe ῍

,K+, =*)  /B4¯°o)*45 CD

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94

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Fig. + Compositional relationship between crystal and saturated solution in the system
FeSO.Al, (SO.)-H,O, expressed in terms of Fe/Al in molar ratio.
 + Al, SO.- FeSO.H,O 
FeῌAl  


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,/ Al, SO.- FeSO.H,O %&'()*+, Occleshaw +3,/ -.%#/01234563 (78, Occleshaw 9:;(<=>?@A FeῌAl B CDB

E+>FGA Fe ῌ Al B(H2I3+,JK Fig. + #$ Figure + KLMNO?@AFeῌAl B*., #FGA FeῌAl BKPQM .R-BK *., ST#$RUVDW:XY+Z

+[=,8#$ \,1234563]^_#- FeῌAl B- *./ #$ ?@A FeῌAl B
K *./ `a#$RUbcde[1234563KM.f [ .BgK *., f *./ A
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thffJ Q + KRf - *., STf[>=.fK{R/  
v=> xJ$-#$ Fe ῌ f Fe ῍#- [$.fKZ, Zi?v(]M,8 J \Rlf K¡\R RffJ (¢Ml£¤f¥¦K§¨#$ .R N>©ª«K¬l ­"®\R>=Z(¯M.fK# f° 1234563fVDW:XY(de[±#¦+ ª«²³´µ(iZ M.f- ª«(¶·Z"f+>v(M¸#¹º»95      !"ῌ #$ %&' ( )*

#+,-./ ( )-012

ῌ 3"456"7 89:%;<=>,12 3? Fe ῌ ῌAl  @A "BCD
& E>FG%H6I: = J+

<"89:%K῏῎LM NOPQ $ R$ !ST"U #V$%UWX%YZ&[ 8\]'=>(^%P_`$ R$ abc) *d+e ,fg h-i jk."lmFn*oY [ /0123-p4qrs9E>tuv1 8<oYwE>5xῌῑῐ῍
;6" yz" +302 : 7{+|}~$> 89p: No. -2 21῍
22.

  +323 :);< =>x?

jk *d+e +302 : @28ABJC08BJDE D
9p\]: No. +3 -1῍...
FG abc) +3// : +3/- H 1 D ,0 IJK9p 8\]L: -- +/-῍+0+.

 +30/ :FGM~$> D9p\]: No. +0 +1῍,*.

Locke, A. J., Martens, W.N. and Frost, R.L. (,**1) : Thermal analysis of halotrichites. Thermochim. Acta, ./3, 0.῍1,.
Lovas, G.A. (+320) : Structural study of halotrichite from Recsk (Matra Mts., N-Hungary). Acta
Geol. Hungarica, ,3, -23῍-32.

N  abO abc)

+300 : /P , -   8¡0 Halotrichite, Alu-nogen );FG<Q¢B£¤¥~$> R¦ § ¨R©

 +1 ,2῍-/.

+3/. : SªT7{9p: 89D: / ,31῍-*0.

I/  ,**3 : «¬­®¯ UV°:W X±

Occleshaw, V. J. (+3,/) : The equilibrium in the systems aluminium sulphate-copper sulphatewater and aluminium sulphate-ferrous sulphate-water at ,/. J. Chem. Soc., Trans., +,1,,/32῍,0*,.

DnFY +31* : D)² .02 p.
abc) ,**2 : \]³<~´!Z µ¶ · ,**1 : ¸K[¹\º]^1»¼

96

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