http://earthwise.bgs.ac.uk/index.php?action=history&feed=atom&title=File%3AP519574.jpg 2026-07-03T00:05:05Z Revision history for this page on the wiki MediaWiki 1.42.3 http://earthwise.bgs.ac.uk/index.php?title=File:P519574.jpg&diff=31740&oldid=prev 2017-07-29T14:53:15Z

<p>User created page with UploadWizard</p> <p><b>New page</b></p><div>=={{int:filedesc}}==<br /> {{Information<br /> |description={{|1=Specimen of slate rock from Ballachulish, Argyllshire, Scotland. This specimen shows clearly the sedimentary bedding, defined by the parallel bands of slghtly paler colors. This was termed&#039;ribboning&#039;by the quarrymen. The specimen is of Precambrian, Dalradian age. British Geological Survey Petrology Collection sample number EMC 5750. Large cubic crystals of yellow metallic pyrite are also present on the slate surface. Bedding is not commonly seen in high quality slates, as it typically occurs at an angle to the slaty cleavage and can sometimes reduce the quality of the slate. However it allows us to see the original nature of the sedimentary deposits from which slate is formed. The colour of slates generally results from the presence of iron-rich minerals; red and purple from fine-grained hematite; grey and blue from variable amounts of pyrite. Oxidation of pyrite can cause red staining. Specimen size: 18x12cm. P519574.}}<br /> |date=2017-07-29 15:51:11<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