Estimated Above Ground WeightsWhere they are given, the estimated above ground* weights of the stones are taken from Appendix 1 of the English Heritage publication entitled:
RESEARCH REPORT SERIES no. 32-2012
STONEHENGE LASER SCAN:
ARCHAEOLOGICAL ANALYSIS REPORT
ENGLISH HERITAGE PROJECT 6457
by Marcus Abbott and Hugo Anderson-Whymark, with contributions from Dave Aspden, Anna Badcock, Tudur Davies, Mags Felter, Rob Ixer, Mike Parker Pearson and Colin Richards.
The data is derived from a laser scan of the monument carried out in 2012. It assumes that the specific gravity of the Sarsens is 2.4 and that the specific gravity of the Bluestones is 3 (dolerite) and 2.4 (rhyolite/rhyolitic tuff).
This publication is available online as a PDF.
* As a rough guide, between a quarter and a third of each stone is below ground so the given weights are somewhat less than the total weight.
Bluestone Rock TypesWhere the bluestone type is given, the information is from Robert Ixer and Richard Bevin's ongoing work on categorising and provenancing. There are too many references to cite here, but a search on Academia.edu for either Robert or Richard will locate many papers.
3D Model ViewerThe 3D models of the stones make use of a feature called "WebGL" which is not supported by all browsers and operating systems. If you have problems viewing the 3D models, try Googling for any known problems with WebGL and your particular flavour of operating system and browser.
For instance, in Chrome on OSX versions lower than 10.8 you may need to go to about:flags and enable "Override software rendering list".