of 16
1
The trace element conundrum of natural
quasicrystals
Simone Tommasini
a
, Luca Bindi
a,b
, Maurizio Petrelli
c
, Paul D. Asimow
d
, and Paul J.
Steinhardt
e
SUPPORTING INFORMATION
2
Figure S1
– Nanometric “finger” of corundum penetrating icosahedrite. Scale bar of 2
m
is shown at the bottom right.
3
Figure S2
– Relative Sensitivity Factors (RSF) normalized to Al (a) and Fe (b) for NIST
SRM 610 silicate glass standard
21
as calibrator reference material, and HOBA, NORTH
CHILE and NIST SRM 1262b as metal alloy reference materials. RSF =
(C
i
/C
re
)/(Int
i
/Int
re
), where C
i
is the concentration of element
i
, and Int
i
is the background-
corrected intensity for the peak used for that element; C
re
is the concentration of the
reference element (Al or Fe), and Int
re
the background-corrected intensity of either Al or
Fe. The RSF are reported for those trace elements available in the metal alloy reference
materials and are compared to those of the NIST SRM 610 reference material. Both Al-
4
and Fe-normalized RSF of elements and elemental ratios, used in this study, of the
metal matrices and silicate glass matrix are in good agreement except for those
elements heterogeneously distributed in the metal alloys (e.g., Zr, Ti).
Figure S3
- Quality control diagram showing the elemental contents determined in four
reference materials (NIST SRM 612, USGS BCR2G, USGS BHVO2G, and USGS
GSD1),
30
and compared to the certified values (see also Table S1).
5
Figure S4
- Time-resolved signals for Al (a), La (b), and Ce (c) of sample NI2_02 (Table
2) acquired during ablation and showing the high-energy transients likely due to the
occurrence of nanoparticles in the ablated volume of QCs.
6
Figure S5
– Chondrite normalized
33
trace element spider-diagram of the unique ultra-
refractory inclusions in Murchison meteorite
37
and in Group II CAIs
31,35
in comparison
with others average CAI composition.
35
The elements are ordered from left to right with
decreasing 50% condensation temperature temperature (T
C
) in a gas of solar
composition at 10
–4
bar.
32
The complementary fractionation of highly refractory
elements is noteworthy and suggests materials processed in a high-temperature
nebular environment.
8
Element
Isotope
mass
NIST
SRM
612
1sd
r ef.
values
Accur acy
%
USGS
GSD
1G
1sd
r ef.
values
Accur acy
%
BCR
2G
1sd
r ef.
values
Accur acy
%
BHVO
2G
1sd
r ef.
values
Accur acy
%
B
11
35.0
0.3
35
0%
58
1
50
16%
5.2
0.5
5.8
10%
5
2
Na
23
101625
850
103858
2%
23950
71
26707
10%
22050
212
23962
8%
15565
233
17806
13%
Mg
25
60
1
77
21%
18660
283
21712
14%
19750
212
21467
8%
39200
990
42994
9%
K
39
64
1
66
3%
25600
990
25300
1%
15950
495
14900
7%
4460
42
4270
4%
Ti
47
42.3
0.5
44
4%
6480
141
7434
13%
12450
212
14100
12%
14385
262
16726
14%
V
51
37.3
0.2
39
4%
38.0
0.3
44
14%
410
10
425
4%
301
9
308
2%
Cr
53
35
1
36
3%
37.1
0.5
42
12%
14
1
17
17%
267
8
293
9%
Mn
55
44.0
0.4
38
16%
222
1
220
1%
1590
14
1550
3%
1349
34
1317
2%
Co
59
34.0
0.3
35
3%
35
1
40
13%
35
1
38
9%
41.2
0.2
44
6%
Zn
66
38.7
0.3
38
2%
50
3
54
7%
153
6
125
22%
112
2
102
10%
Ga
71
36.4
0.2
36
1%
50
1
54
7%
21.5
0.4
23
7%
21
1
22
7%
As
75
33.0
0.5
37
11%
30
1
27
12%
1.0
0.1
0.9
0.2
Rb
85
31.7
0.3
31
1%
35.2
0.2
37.3
6%
47
1
47
1%
8.9
0.3
9.2
4%
Sr
88
80
1
78
2%
65
2
69.4
6%
320
4
342
6%
370
1
396
7%
Y
89
36.6
0.4
38
4%
37.0
0.4
42
12%
30.3
0.4
35
13%
22.5
0.1
26
13%
Zr
90
37
1
38
3%
38
1
42
10%
168
3
184
9%
153.3
0.2
170
10%
Nb
93
34.5
0.1
40
14%
35.0
0.4
42
17%
10.0
0.2
13
20%
14.5
0.6
18
21%
Mo
95
3
5.9
0.3
38
6%
33
1
39
15%
248
9
270
8%
3.7
0.4
3.8
2%
Ag
107
21.1
0.4
22
4%
20.2
0.3
23
12%
0.627
0.5
25%
0.84
0.02
Cd
111
28.1
0.4
28
1%
23
2
18
26%
0.31
0.00
0.2
55%
0.16
0.07
0.1
64%
Sn
120
35
1
38
9%
29
1
29
0%
1.83
0.04
2.6
30%
1.5
0.0
2.6
42%
Sb
121
31.4
0.2
38
17%
33
1
43
24%
0.32
0.01
0.4
8%
0.22
0.01
0.3
27%
Ba
137
38.3
0.2
40
4%
63.0
0.1
67
6%
665
35
683
3%
121
6
131
7%
La
139
37.5
0.2
36
5%
36.5
0.7
39
6%
25
1
25
1%
14.6
0.4
15
4%
Ce
140
37
1
39
3%
37.1
0.6
41.4
10%
51
2
53
4%
34
1
38
9%
Pr
141
35.8
0.5
37
4%
38.6
0.2
45
14%
6.1
0.4
6
.7
9%
4.5
0.1
5.4
16%
Nd
145
34.9
0.4
36
3%
39.8
0.0
44.7
11%
26
2
29
11%
22
1
25
11%
Sm
147
36
1
38
4%
41.7
0.0
47.8
13%
5.8
0.3
6.6
13%
5.58
0.01
6.1
9%
Eu
153
36
1
35
4%
38.0
0.6
41
7%
1.83
0.08
2.0
7%
1.96
0.02
2.1
6%
Gd
157
36
1
37
1%
43.7
0.4
50.7
14%
5.8
0.3
6.7
13%
5.6
0.3
6.2
9%
Tb
159
37
1
36
2%
43.1
0.2
47
8%
0.93
0.09
1.0
9%
0.85
0.03
0.9
7%
Dy
163
33.9
0.5
36
6%
44.8
0.1
51.2
13%
5.6
0.1
6
12%
4.8
0.3
5.3
10%
Ho
165
37.0
0.4
38
3%
44.1
0.1
49
10%
1.14
0.02
1.3
11%
0.90
0.01
1.0
8%
Er
166
34.6
0.4
38
9%
32.4
0.1
40.1
19%
3.1
0.1
3.7
16%
2.18
0.04
2.6
15%
Tm
169
34
1
38
11%
42.0
0.3
49
14%
0.45
0.04
0.5
12%
0.29
0.01
0.3
16%
Hf
178
35
1
35
0%
35.8
0.4
39
8%
4.4
0.4
4.8
10%
4.19
0.06
4.3
3%
Ta
181
37
1
40
8%
38.1
0.5
40
5%
0.69
0.03
0.8
11%
1.04
0.01
1.2
9%
W
182
38.0
0.5
40
5%
38.2
0.1
43
11%
0.500 0.001
0.5
0%
0.24
0.02
0.2
3%
Re
185
6.3
0.1
6.6
5%
4.3
0.1
0.0098
0.01
bdl
0.0005
Tl
205
15.0
0.1
15
1%
0.81
0.05
0.9
10%
0.24
0.02
0.3
22%
0.027 0.006
Pb
208
38
1
39
3%
46
2
50
9%
10.4
0.4
11
5%
1.72
0.02
1.7
1%
Bi
209
30
1
30
1%
30
1
35
13%
0.05
0.05
10%
0.
04
0.01
310%
Th
232
36
1
38
4%
39
2
41
5%
5.4
0.3
5.9
8%
1.11
0.03
1.2
9%
Table S1
– Trace element analyses (
μ
g/g) of reference standards.
9
Table S2
-
First Stage: end member
proxies
and trace element content (CI normalized)
of the mixing process
e
n
d
m
e
m
b
e
r
p
r
o
x
i
e
s
Z
r
N
d
E
r
T
m
C
r
Z
r
/
C
r
T
m
/
E
r
N
d
/
E
r
M
u
r
c
h
i
s
o
n
a
v
g
1
-
3
9
0
2
7
.
6
7
3
0
6
9
3
1
9
0
.
2
6
3
4
7
7
0
.
1
0
4
0
.
0
0
2
5
C
I
1
1
1
1
1
a
v
g
C
A
I
I
I
1
.
8
8
3
9
.
0
1
1
.
5
5
3
2
.
3
0
0
.
4
6
4
.
0
9
2
0
.
7
7
2
5
.
0
9
a
v
g
C
A
I
1
9
.
3
1
1
9
.
1
4
2
0
.
7
2
2
0
.
4
2
0
.
2
2
8
8
.
2
0
.
9
9
0
.
9
2
C
A
I
I
I
2
0
%
-
C
I
8
0
%
1
.
1
8
8
.
6
0
1
.
1
1
7
.
2
6
0
.
8
9
1
.
3
2
6
.
5
3
7
.
7
4
C
A
I
I
I
C
I
1
0
0
%
0
%
1
.
8
8
3
9
.
0
1
1
.
5
5
3
2
.
3
0
0
.
4
6
4
.
0
9
2
0
.
7
7
2
5
.
0
9
8
0
%
2
0
%
1
.
7
0
3
1
.
4
1
1
.
4
4
2
6
.
0
4
0
.
5
7
3
.
0
0
1
8
.
0
3
2
1
.
7
5
6
0
%
4
0
%
1
.
5
3
2
3
.
8
1
1
.
3
3
1
9
.
7
8
0
.
6
8
2
.
2
6
1
4
.
8
4
1
7
.
8
6
4
0
%
6
0
%
1
.
3
5
1
6
.
2
1
1
.
2
2
1
3
.
5
2
0
.
7
8
1
.
7
2
1
1
.
0
6
1
3
.
2
6
2
0
%
8
0
%
1
.
1
8
8
.
6
0
1
.
1
1
7
.
2
6
0
.
8
9
1
.
3
2
6
.
5
3
7
.
7
4
0
%
1
0
0
%
1
1
1
1
1
1
1
1
C
A
I
I
I
-
C
I
M
u
r
c
h
i
s
o
n
1
0
0
%
0
%
3
%
0
.
0
3
5
0
.
2
5
8
0
.
0
3
3
0
.
2
1
8
0
.
0
2
6
8
1
.
3
2
6
.
5
3
7
.
7
4
9
9
.
9
5
%
0
.
0
5
%
3
%
0
.
0
4
9
0
.
2
5
8
0
.
0
7
9
0
.
2
2
2
0
.
0
2
6
8
1
.
8
2
2
.
8
0
3
.
2
5
9
9
.
8
%
0
.
2
%
3
%
0
.
0
8
9
0
.
2
5
8
0
.
2
1
7
0
.
2
3
6
0
.
0
2
6
7
3
.
3
4
1
.
0
9
1
.
1
9
9
9
.
5
%
0
.
5
%
3
%
0
.
1
7
0
0
.
2
5
8
0
.
4
9
4
0
.
2
6
4
0
.
0
2
6
7
6
.
3
9
0
.
5
4
0
.
5
2
9
9
%
1
%
3
%
0
.
3
0
5
0
.
2
5
8
0
.
9
5
4
0
.
3
1
1
0
.
0
2
6
6
1
1
.
5
0
.
3
3
0
.
2
7
9
8
%
2
%
3
%
0
.
5
7
5
0
.
2
5
8
1
.
8
7
4
0
.
4
0
5
0
.
0
2
6
4
2
1
.
8
0
.
2
2
0
.
1
4
9
5
%
5
%
3
%
1
.
3
8
6
0
.
2
5
7
4
.
6
3
6
0
.
6
8
5
0
.
0
2
5
8
5
3
.
7
0
.
1
5
0
.
0
6
9
0
%
1
0
%
3
%
2
.
7
3
6
0
.
2
5
5
9
.
2
3
8
1
.
1
5
2
0
.
0
2
4
9
1
1
0
0
.
1
2
0
.
0
2
8
8
0
%
2
0
%
3
%
5
.
4
3
7
0
.
2
5
3
1
8
.
4
4
2
.
0
8
5
0
.
0
2
3
0
2
3
7
0
.
1
1
0
.
0
1
4
0
%
1
0
0
%
3
%
2
7
.
0
5
0
.
2
3
0
9
2
.
0
8
9
.
5
5
5
0
.
0
0
7
8
3
4
7
7
0
.
1
0
0
.
0
0
2
C
A
I
I
I
M
u
r
c
h
i
s
o
n
1
0
0
%
0
%
3
%
0
.
0
5
6
1
.
1
7
0
0
.
0
4
7
0
.
9
6
9
0
.
0
1
3
8
4
.
0
9
2
0
.
8
2
5
.
1
9
9
.
9
%
0
.
1
%
3
%
0
.
0
8
3
1
.
1
6
9
0
.
1
3
9
0
.
9
7
8
0
.
0
1
3
8
6
.
0
5
7
.
0
5
8
.
4
3
9
9
.
8
%
0
.
2
%
3
%
0
.
1
1
0
1
.
1
6
9
0
.
2
3
1
0
.
9
8
6
0
.
0
1
3
8
8
.
0
1
4
.
2
7
5
.
0
6
9
9
.
5
%
0
.
5
%
3
%
0
.
1
9
1
1
.
1
6
6
0
.
5
0
7
1
.
0
1
2
0
.
0
1
3
8
1
3
.
9
2
.
0
0
2
.
3
0
9
9
%
1
%
3
%
0
.
3
2
6
1
.
1
6
1
0
.
9
6
7
1
.
0
5
5
0
.
0
1
3
7
2
3
.
7
1
.
0
9
1
.
2
0
9
8
%
2
%
3
%
0
.
5
9
6
1
.
1
5
2
1
.
8
8
7
1
.
1
4
1
0
.
0
1
3
7
4
3
.
6
0
.
6
0
0
.
6
1
9
7
%
3
%
3
%
0
.
8
6
6
1
.
1
4
2
2
.
8
0
8
1
.
2
2
7
0
.
0
1
3
6
6
3
.
6
0
.
4
4
0
.
4
1
9
5
%
5
%
3
%
1
.
4
0
6
1
.
1
2
3
4
.
6
4
9
1
.
3
9
8
0
.
0
1
3
5
1
0
4
0
.
3
0
0
.
2
4
9
3
%
7
%
3
%
1
.
9
4
6
1
.
1
0
5
6
.
4
8
9
1
.
5
7
0
0
.
0
1
3
4
1
4
5
0
.
2
4
0
.
1
7
9
0
%
1
0
%
3
%
2
.
7
5
5
1
.
0
7
6
9
.
2
5
0
1
.
8
2
8
0
.
0
1
3
2
2
0
9
0
.
2
0
0
.
1
2
8
0
%
2
0
%
3
%
5
.
4
5
4
0
.
9
8
2
1
8
.
4
5
2
.
6
8
6
0
.
0
1
2
6
4
3
3
0
.
1
5
0
.
0
5
3
7
0
%
3
0
%
3
%
8
.
1
5
3
0
.
8
8
8
2
7
.
6
6
3
.
5
4
5
0
.
0
1
2
0
6
8
0
0
.
1
3
0
.
0
3
2
0
%
1
0
0
%
3
%
2
7
.
0
5
0
.
2
3
0
9
2
.
0
8
9
.
5
5
5
0
.
0
0
7
8
3
4
7
7
0
.
1
0
0
.
0
0
2
C
A
I
I
I
C
A
I
1
0
0
%
0
%
3
%
0
.
0
5
6
1
.
1
7
0
0
.
0
4
7
0
.
9
6
9
0
.
0
1
3
8
4
.
0
9
2
0
.
8
2
5
.
1
9
0
%
1
0
%
3
%
0
.
1
0
9
1
.
1
1
1
0
.
1
0
4
0
.
9
3
3
0
.
0
1
3
1
8
.
3
1
8
.
9
6
1
0
.
7
8
0
%
2
0
%
3
%
0
.
1
6
1
1
.
0
5
1
0
.
1
6
2
0
.
8
9
8
0
.
0
1
2
4
1
3
.
0
5
.
5
5
6
.
5
0
7
0
%
3
0
%
3
%
0
.
2
1
3
0
.
9
9
2
0
.
2
1
9
0
.
8
6
2
0
.
0
1
1
6
1
8
.
3
3
.
9
3
4
.
5
3
6
0
%
4
0
%
3
%
0
.
2
6
6
0
.
9
3
2
0
.
2
7
7
0
.
8
2
6
0
.
0
1
0
9
2
4
.
4
2
.
9
9
3
.
3
7
5
0
%
5
0
%
3
%
0
.
3
1
8
0
.
8
7
2
0
.
3
3
4
0
.
7
9
1
0
.
0
1
0
2
3
1
.
2
2
.
3
7
2
.
6
1
4
0
%
6
0
%
3
%
0
.
3
7
0
0
.
8
1
3
0
.
3
9
2
0
.
7
5
5
0
.
0
0
9
5
3
9
.
1
1
.
9
3
2
.
0
8
3
0
%
7
0
%
3
%
0
.
4
2
2
0
.
7
5
3
0
.
4
4
9
0
.
7
1
9
0
.
0
0
8
7
4
8
.
4
1
.
6
0
1
.
6
8
2
0
%
8
0
%
3
%
0
.
4
7
5
0
.
6
9
3
0
.
5
0
6
0
.
6
8
4
0
.
0
0
8
0
5
9
.
2
1
.
3
5
1
.
3
7
1
0
%
9
0
%
3
%
0
.
5
2
7
0
.
6
3
4
0
.
5
6
4
0
.
6
4
8
0
.
0
0
7
3
7
2
.
3
1
.
1
5
1
.
1
2
0
%
1
0
0
%
3
%
0
.
5
7
9
0
.
5
7
4
0
.
6
2
1
0
.
6
1
2
0
.
0
0
6
6
8
8
.
2
0
.
9
9
0
.
9
2
b
a
r
r
e
n
d
e
c
a
g
o
n
i
t
e
b
a
r
r
e
n
i
c
o
s
a
h
e
d
r
i
t
e
m
i
x
t
u
r
e
s
%
n
a
n
o
p
a
r
t
i
c
l
e
s
%
n
a
n
o
p
a
r
t
i
c
l
e
s
%
n
a
n
o
p
a
r
t
i
c
l
e
s
10
footnote
: bold digits are the composites indicated in Figures 5 and 6.
Table S3 -
Second Stage: starting material, partition coefficients (Ds), and trace element
content (CI normalized) at different aggregated vapor mass fractions (F)
S
t
a
r
t
i
n
g
m
a
t
e
r
i
a
l
C
r
S
b
P
b
B
i
S
b
/
C
r
B
i
/
C
r
P
b
/
C
r
C
I
1
1
1
1
a
v
g
S
C
S
1
.
6
1
4
.
4
0
1
3
.
6
6
8
.
6
3
2
.
7
3
5
.
3
5
8
.
4
7
S
C
S
P
1
1
7
1
.
8
3
8
.
5
9
7
3
.
1
6
2
.
5
4
.
7
1
3
4
.
2
4
0
.
0
S
C
S
P
5
6
1
.
3
0
1
3
.
9
1
8
.
2
6
3
.
8
6
1
0
.
6
6
2
.
9
6
6
.
3
4
P
a
r
t
i
t
i
o
n
c
o
e
f
f
i
c
i
e
n
t
(
D
)
e
s
t
i
m
a
t
e
s
a
t
d
i
f
f
e
r
e
n
t
F
F
=
5
%
1
0
.
0
0
8
3
6
0
.
0
2
3
2
6
0
.
0
1
0
6
1
F
=
1
%
1
0
.
0
0
1
6
5
0
.
0
0
4
6
5
0
.
0
0
2
1
0
F
=
0
.
1
%
1
0
.
0
0
0
1
6
0
.
0
0
0
4
6
0
.
0
0
0
2
1
A
g
g
r
e
g
a
t
e
d
f
r
a
c
t
i
o
n
a
l
e
v
a
p
o
r
a
t
i
o
n
-
C
I
c
o
l
l
i
s
i
o
n
%
n
a
n
o
p
a
r
t
i
c
l
e
s
F
=
5
%
1
%
0
.
0
1
0
0
.
2
0
0
0
.
1
7
8
0
.
1
9
8
1
9
.
9
6
1
9
.
8
4
1
7
.
7
9
F
=
1
%
1
%
0
.
0
1
0
0
.
9
9
8
0
.
8
8
5
0
.
9
9
2
9
9
.
8
9
9
.
2
8
8
.
5
F
=
0
.
1
%
1
%
0
.
0
1
0
9
.
9
8
8
.
8
4
9
.
9
2
9
9
8
9
9
2
8
8
4
A
g
g
r
e
g
a
t
e
d
f
r
a
c
t
i
o
n
a
l
e
v
a
p
o
r
a
t
i
o
n
-
a
v
g
S
C
S
c
o
l
l
i
s
i
o
n
%
n
a
n
o
p
a
r
t
i
c
l
e
s
F
=
5
%
1
%
0
.
0
1
6
0
.
8
7
8
2
.
4
3
1
1
.
7
1
2
5
4
.
5
1
0
6
1
5
1
F
=
1
%
0
.
3
%
0
.
0
0
5
1
.
3
1
7
3
.
6
2
7
2
.
5
6
7
2
7
2
5
3
1
7
5
0
F
=
0
.
1
%
0
.
5
%
0
.
0
0
8
2
1
.
9
6
6
0
.
3
8
4
2
.
7
8
2
7
2
3
5
3
0
5
7
4
8
9
A
g
g
r
e
g
a
t
e
d
f
r
a
c
t
i
o
n
a
l
e
v
a
p
o
r
a
t
i
o
n
-
S
C
S
s
a
m
p
l
e
A
A
S
-
3
8
-
2
0
7
-
P
1
1
7
c
o
l
l
i
s
i
o
n
%
n
a
n
o
p
a
r
t
i
c
l
e
s
F
=
5
%
1
%
0
.
0
1
8
1
.
7
1
5
1
3
.
0
1
1
2
.
3
9
4
9
3
.
9
6
7
9
7
1
3
F
=
1
%
0
.
3
%
0
.
0
0
5
2
.
1
4
3
1
6
.
1
8
1
5
.
4
9
4
6
9
3
3
9
3
3
5
4
4
F
=
0
.
1
%
0
.
1
%
0
.
0
0
2
8
.
5
7
6
4
.
6
3
6
1
.
9
5
4
6
9
4
3
3
9
2
6
3
5
3
9
8
A
g
g
r
e
g
a
t
e
d
f
r
a
c
t
i
o
n
a
l
e
v
a
p
o
r
a
t
i
o
n
-
S
C
S
s
a
m
p
l
e
A
A
S
-
6
2
-
6
1
-
P
5
6
c
o
l
l
i
s
i
o
n
%
n
a
n
o
p
a
r
t
i
c
l
e
s
F
=
5
%
1
%
0
.
0
1
3
2
.
7
7
5
1
.
4
7
1
0
.
7
6
6
2
1
3
5
8
.
7
1
1
3
F
=
1
%
1
%
0
.
0
1
3
1
3
.
8
7
7
.
3
1
3
.
8
3
1
0
6
4
2
9
4
5
6
1
F
=
0
.
1
%
0
.
2
%
0
.
0
0
3
2
7
.
7
5
1
4
.
6
1
7
.
6
6
1
0
6
3
8
2
9
3
6
5
6
0
2
11
Supplementary Text
A note on synthetic
vs
natural QCs –
Reflected light images of the two specimens of
synthetic icosahedrite and two specimens of synthetic decagonite are shown in Figure
S6. All the syntheses were via solid state reaction beginning from high-purity metals,
namely: (i) icosahedral Al
63
Cu
24
Fe
13
(atomic %) synthesized in Ar at 980 °C and
annealed for several hours at 850 °C (labeled SI1; SI = synthetic icosahedrite); (ii)
icosahedral Al
65
Cu
23
Fe
12
(atomic %) from the Sigma-Aldrich Company (#757934-10G),
synthesized in Ar at 800 °C (labeled SI2); (iii) decagonal Al
72
Ni
24
Fe
4
(atomic %) from the
Goodfellow Company (particle diameter <500
m), synthesized in Ar at 1350 °C
(labeled SD1; SD = synthetic decagonite); (iv) decagonal Al
72
Ni
24
Fe
4
(atomic %)
synthesized in Ar at 1400 °C for 10 hours, quenched, reground, fired again at 1400 °C
for 6 hours, and finally quenched (labeled SD2).
12
The major and trace element analyses of the four synthetic quasicrystals are reported
in Tables S4 and S5, respectively. The trace element content of the Khatyrka QCs is
significantly different from that of synthetic QCs; most elements occurring in the
Khatyrka QCs are below detection limit in synthetic QCs, and the ratios of natural to
synthetic abundance of those few elements occurring in both types of QC deviate
significantly from unity (Fig. S7). Synthetic icosahedrite spot analyses contain
detectable amounts of Zn, Ag, Sn, Pb and Bi, as expected of a material synthesized
from Cu starting material. The source of high levels of boron is unclear; although this
element is a common surface contaminant, all the samples have been carefully polished
before analysis and the B signal does not decay with continued ablation. The synthetic
decagonite spot analyses contain measurable levels of Co, expected for material
synthesized from Fe and Ni starting material.
In addition to the trace element analyses and the arguments presented in the
Introduction section on the natural origin of the studied QCs,
1,5-8,15
we wish to highlight
the following indisputable facts: (i) the first natural quasicrystals samples were
unearthed in 1979, whereas quasicrystals were not discovered until 1984, so the
13
occurrence of quasicrystals in the 1979 samples could not have been intentional; (ii) no
natural terrestrial source of icosahedrite or decagonite has ever been reported; (iii) as
for synthetic samples made on Earth, there is no industrial production of Al-Cu alloys
with composition corresponding to icosahedrite, khatyrkite, stolperite, and cupalite
because they are too brittle to have practical value; (iv) in fact, the only known materials
on Earth with the compositions of the quasicrystalline phases in Khatyrka are those
synthetic samples fabricated by chemical/metallurgical companies for specific purposes
such as this study, production of which evidently began after 1984.
14
Figure S6
- Reflected light images of the four synthetic quasicrystals (icosahedral
phase: SI1 and SI2; decagonal phase: SD1 and SD2) investigated. Scale bar is
indicated.
15
Figure S7
- Elemental content in natural QC ratioed to synthetic QC (decagonite (a),
icosahedrite (b)). The elemental content of each data point of the two natural QCs
(Table 2) has been divided by the average content of the two synthetic QCs (Table S5).
In both panels, those elements below detection limit in synthetic QCs are plotted to the
top off-scale light coloured area, whereas those elements below detection limit in
natural QCs are plotted to the bottom off-scale light coloured area. Most of the elements