http://earthwise.bgs.ac.uk/index.php?action=history&feed=atom&title=File%3AP519603.jpg 2026-07-03T01:54:36Z Revision history for this page on the wiki MediaWiki 1.42.3 http://earthwise.bgs.ac.uk/index.php?title=File:P519603.jpg&diff=31767&oldid=prev 2017-07-29T15:21:43Z

<p>User created page with UploadWizard</p> <p><b>New page</b></p><div>=={{int:filedesc}}==<br /> {{Information<br /> |description={{|1=Specimen of roofing slate from Aberfoyle Slate Quarries, Perthshire, Scotland. Greenish grey slate sample with reflective cleavage surface disrupted by the presence of ribboning or original bedding. The specimen is of Precambrian, Dalradian age. British Geological Survey Petrology Collection sample number EMC 5778. The intersection of bedding on the cleavage surface shows that bedding and cleavage are generally not related in a slate (although they can occasionally be parallel). This is unlike a stone-slate or flagstone where the splitting ability depends entirely upon the weakness along the bedding planes. A slaty cleavage forms in response to heat and pressure as a result of metamorphic processes. The cleavage surface then becomes the weakest plane in the rock, along which it can split most easily. Specimen size: 15x15cm. P519603.}}<br /> |date=2017-07-29 15:59:46<br /> |source=British Geological Survey<br /> |author=British Geological Survey<br /> |permission=<br /> |other versions=<br /> }}<br /> <br /> =={{int:license-header}}==<br /> {{subst:Custom license marker added by UW}}<br /> {{BGS}}<br /> <br /> [[Category:Uploaded with UploadWizard]]</div>

Scotfot