Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-24T13:13:53.205Z Has data issue: false hasContentIssue false

A fusion method for preparing glass samples of peridotitic and picritic rock compositions for bulk analysis

Published online by Cambridge University Press:  05 July 2018

N. W. A. Odling*
Affiliation:
Dept of Geology and Geophysics, University of Edinburgh, West Mains Rd., Edinburgh, EH9 3JW, Scotland, UK

Abstract

A design for a micro furnace and a fusion technique are described by which silicate materials (in particular picritic and peridotitic rock compositions) may be fused and quenched to a homogeneous glass without significant loss of components, for the purposes of bulk analysis. The furnace consists of a Pt wire electrical resistance heater mounted in a furnace assembly which is fitted to a microscope stage. Microscopic examination of the sample during the fusion process allows the sample to be quenched as soon as all crystalline material has been fused and thus minimizes the loss of iron and alkalis due either to over-heating or prolonged fusion time. Analysis of glass beads of a model peridotite composition (analysed independently by X-ray fluorescence analysis) shows that for typical fusion times (5–10 seconds) the bulk composition is preserved at distances of > 25 µm from the margins of the glass beads. Analysis of natural rock powders of known composition shows that the method can be used to analyse whole rock compositions. The furnace is simple to construct and cheap to run and provides a simple and rapid method of producing glass samples for bulk analysis.

Type
Geochemistry
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Fitton, G. and Dunlop, H. M. (1985) The Cameroon line, West Africa, and its bearing on the origin of oceanic and continental alkali basalt basalt. Earth Planet. Sci. Lett., 72, 23–8.CrossRefGoogle Scholar
Govindaraju, K. (1989) 1989 compilation of working values and sample description of 272 geostandards. Geostandards Newsletter, 13 (special issue), 1 — 113.Google Scholar
Green, D. H. (1973) Experimental melting studies on a model upper mantle composition at high pressure under water-saturated and water undersaturated conditions. Earth Planet. Sci. Lett., 19, 37–53.CrossRefGoogle Scholar
Hamilton, D. L. and Henderson, C. M. B. (1968) The preparation of silicate compositions by a gelling method. Mineral. Mag., 36, 832–38.Google Scholar
Mysen, B., Ryerson F. J. and Virgo, D. (1981) The structural role of phosporus in silicate melts. Amer. Mineral. 66, 106–17.Google Scholar
Nicholls, I. A. (1974) A direct fusion method of preparing silicate rock glasses for energy-dispersive electron microprobe analysis. Chem. Geol., 14, 151–7.CrossRefGoogle Scholar
Ryerson, F. J. (1985) Oxide solution mechanisms in silicate melts: systematic variations in the activity of coefficient of SiO2 . Geochim. Cosmochim. Ada, 49, 637–49.CrossRefGoogle Scholar
Weast, R. C. (1974) Handbook of chemistry and Physics, 56th. Edition. Edit.Google Scholar
Weast, R.C. CRC Press Inc., Cleveland, Ohio, USA.Google Scholar
Welch, J. H. (1954) A simple microscope attachment for observing high temperature phenomena. J. Sci. Instrument., 31, 458.CrossRefGoogle Scholar