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Gold single crystal 79Au196.967
Known to ancient civilizations.
[Anglo-Saxon: gold; Latin: aurum]
French: or
German: gold
Italian: aro
Spanish: aro
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Description: Gold is a soft metal with a characteristic shiny yellow colour.
It has the highest malleability and ducility of any element, and can be beaten into
a film only microns thick. Gold is unaffected by air, water, acids (exept aqua regia,
HNO3-HCl) and alkalis. It is used as bullion, in jewellery, electronics and
glass, to colour it and as a heat reflector.
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Metal single crystal properties
| State: |
single crystal |
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| Crystal structure: |
fcc |
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| Production method: |
Czochralski |
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| Standard size: |
diameter 10-20mm
thickness 1-2mm |
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| Orientation: |
(100), (110) and (111) |
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| Orientation accuracy: |
<2°, <1°, <0.5° or <0.1° |
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| Polishing: |
as cut, one or two sides polished |
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| Roughness of surface: |
<0.03µm |
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| Purity: |
99.999% |
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| Typical analysis (ppm): |
Ag 4.20
Al 0.20
Ca 0.30
Cd < 0.1
Cl 0.16
Co 0.03
Cu 1.30
Fe 0.73
K 0.40
Mg 0.02
Mn 0.04 |
Mo 0.06
Na 0.10
Ni 0.05
Pd 0.25
Rh 0.10
S 0.13
Si 0.51
Ti 0.01
V 0.02
Zn 0.05
Au balance |
Further Materials properties
| Crystal structure: |
(cell dimensions/pm), space group, f.c.c. (a=407.833), Fm3m |
| X-ray diffractions mass absorption coefficients: |
CuKa 208 (µ/r) / cm2g-1
MoKa 115 (µ/r) / cm2g-1
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| Neutron scattering length: |
0.763 b/10-12 cm |
| Thermal neutron capture cross-section: |
98.7 sa / barns |
| Density: |
19.3 g/cm3 |
| Melting point: |
1064.43 °C / 1337.58 °K |
| Boiling point: |
2806.85 °C / 3080 °K |
| Molar volume: |
10.19 cm3 |
| Thermal conductivity: |
317 [300 K] Wm-1K-1 |
| Coefficient of linear thermal expansion: |
14.16 x 10-6 K-1 |
| Electrical resistivity: |
2.35x10-8 [293 K] Wm |
| Mass magnetic susceptibility: |
-1.78 x 10-9(s) kg-1m3 |
| Young's modulus: |
78.5 GPa |
| Rigidity modulus: |
26.0 GPa |
| Bulk modulus: |
171 GPa |
| Poisson's ratio: |
0.42 GPa |
| Radii: |
Au3+ 91; Au+ 137; atomic 144; covalent 134 |
| Electronegativity: |
2.54 (Pauling); 1.42 (Allred); 5.77 eV (absolute) |
| Effective nuclear charge: |
4.20 (Slater); 10.94 (Clementi); 15.94 (Froese-Fischer) |
| Number of Isotopes (incl. nuclear isomers): |
39 |
| Issotope mass range: |
176 -> 204 |
Biological data
| Biological role: |
none, but acts to stimulate metabolism |
| Toxicity |
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| Toxic intake: |
gold metal and gold salts generally have low toxicity |
| Lethal intake: |
n.a. |
| Hazards: |
Gold is poorly absorbed by the body and poisoning by gold compounds is very rare.
Gold-based anti-arthritics can cause liver damage and kidney damage.
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| Level in humans |
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| Blood: |
(0.1 - 4.2) x 10-4mg dm-3 |
| Bone: |
0.016 p.p.m. |
| Liver: |
0.0004 p.p.m. |
| Muscle: |
n.a. |
| Daily dietary intake : |
n.a., but very low |
Total mass of element in average
[70 kg] person: |
0.2 mg |
Geological data
| Minerals: |
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| Mineral |
Formula |
Density |
Hardness |
Crystal apperance |
| Gold |
Au |
19.3 |
2.5 - 3 |
cub., met. white |
| Sylvanite |
AgAuTe4 |
8.16 |
1.5 - 2 |
hex., met. white |
| Chief ore: |
quartz veins in extrusive rocks
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| World production: |
1400 tonnes/year |
| Main mining areas: |
South Africa, USA, Canada, Russia |
| Reserves: |
15000 tonnes |
| Specimen: |
available as foil, powder, rod and shot.
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| Abundances |
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| Sun: |
5.6 (relative to H = 1 x 1012) |
| Earth's crust: |
0.0011 ppm |
| Seawater: |
1 x 10-5 p.p.m. |
Residence time:: |
n.a. |
| Classification: |
n.a. |
| Oxidation state: |
I |
Other sizes and specifications on request
© 1996 - 2008 MaTecK GmbH - Im Langenbroich 20 - D-52428 Juelich - phone: +49 (0) 2461 / 9352-0 - fax: +49 (0) 2461 / 9352-11 - Contact: info@mateck.de
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