Analytical Suite Metadata

GSC atomic emission spectrography: Ag, B, Co, Cr, Mn, Ni, Sn



Geological Survey of Canada, atomic emission spectrography, using a Jarrell-Ash instrument; sample excitation by means of a direct current arc; seven elements measured

General Methodology:

A total energy DC arc semiquantitative method was used utilizing a 1.5-meter grating spectrograph. A 10 mg sample of ground stream sediment was mixed with 20 mg of graphite, packed into a carbon electrode, and capped with a 20 mg buffer mixture of CaC03 and graphite. The loaded electrode was preheated at 450°C to oxidize the organic matter in the sample, and thus allow the arcing to proceed smoothly without loss of material from the electrode cavity.  The electrode was removed from the furnace after 45 minutes and cooled. Two drops of a saturated solution of magnesium nitrate in absolute ethyl alcohol were added in order to promote the smooth burning of the sample. The electrode was then placed under an infrared heat lamp for at least five minutes to evaporate the alcohol.  The samples were then arced at 15 amps, and the spectra recorded on 35 mm Kodak Spectrum Analysis Film No. 1. Unknown spectra were compared to a synthetically prepared series of spectra ranging from 10,000 ppm down to 0.5 ppm for each of the elements analysed.

[description taken from GSC Paper 65-42; see also USGS Bulletin 1084-G]

Instrument:

Sample material: solid

Sample weight: unstated


Analytical Technique:

Hierarchical classification

Technique >> Spectroscopy >> Electromagnetic radiation >> Visible-ultraviolet >> Atomic >> Emission >> Powder D-C Arc

Children

None


Analytical Decomposition:

Hierarchical classification

Decomposition >> None

Children

None


Analytical Methods:

IndexMethod OrderMethod IDQuantityDetection Limit
1  2490     Ag_spec  0.5
2  2491     B_spec  7
3  2492     Co_spec  7
4  2493     Cr_spec  10
5  2494     Mn_spec  20
6  2495     Ni_spec  2
7  2496     Sn_spec  15

Associated Analytical Packages:

IndexPackage IDPackage Name
1  272     GSC spectrography and colorimetry
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