OpenLearn will be unavailable from 8am to 10am on Wednesday 18 March due to a website upgrade.
As part of the upgrade your OpenLearn profile page is changing, as explained in this article.
Personalise your OpenLearn profile, save your favourite content and get recognition for your learning
By understanding the ways in which minerals combine to form rocks like the way words link to form sentences, we can start to unravel the secrets of the earth.