http://www.basicplanet.com/
http://geology.com/
https://www.accuweather.com/en/weather-news/top-5-most-expensive-natural-d/47459
http://earthsky.org/earth/top-five-natural-disasters-of-2011
https://mineralseducationcoalition.org/mining-minerals-information/periodic-table-of-the-elements/
http://education.jlab.org/itselemental/index.html
http://www.rsc.org/chemsoc/visualelements/pages/pertable_fla.html
http://www.chemicool.com/
http://www.chem4kids.com/files/elem_intro.html