Aspects of the Petrology and Geochemistry of Greenstones: with special reference to SW England and Wales

• Main Author: P.A. Floyd
• Format: Article
• Language: English
• Published: University of York 2009-09-01
• Series: Internet Archaeology
• Subjects: archaeology; Greenstone; meta-dolerite; petrological variation; geochemical fingerprinting; low-grade alteration; axe-sources; SW England; Wales
• Online Access: http://intarch.ac.uk/journal/issue26/floyd_index.html

The use of texture, petrology and geochemistry of Neolithic greenstone hand axes, to determine provenance, is well established. However, as many UK greenstones are essentially meta-dolerites (mildly metamorphosed medium-grained basic rocks) it is often necessary to consider the type and degree of alteration superimposed on the primary igneous mineralogy to establish different petrological groups of axes. In particular, alteration and texture can be highly variable in any one large outcrop that might have been used for the manufacture of axes. Similarly, geochemical fingerprinting of axes and subsequent comparison with known outcrops will only be successful if sufficient chemical data are available from any suspected source region when the full range of natural variation has been ascertained.