Silicon, Si

Last changed: 30 November 2021

Known issues with the parameter and/or important method changes

Summary of problems with the silicon analysis at the Geochemical laboratory during 2005-2010 (in Swedish).

Method comparison from the change to optical ICP (in Swedish).

Current method of measurement (inductively coupled plasma)

Valid since May 2016 (valid for samples from January 2016)
Method: ICP-MS, SS-EN ISO 17294-2:2005
Instrument: Agilent.

Previous methods

Previous methods (inductively coupled plasma)

2014 01 - 2015 12
Method: ICP (inductively-coupled plasma), SS-EN ISO 11885:2009
Instrument: PerkinElmer OPTIMA 2100

Previous methods (molybdate-reactive silicon)

The forms of silicon that occur in natural waters exhibit highly variable reactivity with different analytical reagents. Our earlier method measured so-called molybdate-reactive silicon, which represents the amount of dissolved silicon.

2007 01 - 2013 12
Method: Bran & Leubbe Method G-177-96 rev. 8 (Multitest MT 19)
Instrument: Autoanalyzer 3 (upgraded Autoanalyzer II).
NB: Samples conserved with H2SO4.

1995-01 – 2006-12
Method: Bran & Leubbe Industrial Method No. 811-86T.
Instrument: Technicon Traacs 800.
NB: Water samples converved with HgCl2 until 1996, and with H2SO4 since 1997.

1987-01 – 1994-12
Method: Standard Methods 12th Ed. 1965. Henriksen, A: Automatic Modification.
Instrument: Technicon Autoanalyzer II.
NB: Water samples converved with HgCl2.

1971-01 – 1986-12
Method: Standard Methods 12th Ed. 1965. Henriksen, A: Automatic Modification.
Instrument: Technicon Autoanalyzer I.
NB: Water samples converved with HgCl2.

1965-01 – 1970-12
Method: Karlgren, L. 1961, Vattenkemiska analysmetoder (Hydrochemical Analytical Methods, in Swedish). Fotometrisk bestämning av molbyldatreaktivt kisel (Photometric determination of molbyldate-reactive silicon, in Swedish).
NB: Water samples converved with HgCl2.