Crystal structure of scolecite, a zeolite mineral.
Dark blue: Si, light blue: Al, green: Ca, red: O, light pink: H.
The crystal structure was produced in the freeware [Vesta](http://jp-minerals.org/vesta/en/), using crystallograpic data from Stuckenschmidt et al. (1997), downloaded from the [American Mineralogist Crystal Structure Database](http://rruff.geo.arizona.edu/AMS/amcsd.php).