An attempt to make some quartz crystal models. See the nice article, "The Quartz Page", by Amir C Akhavan at http://www.quartzpage.de/index.html - especially the Introduction to Crystals. OpenSCAD code is provided. These crystals exhibit only faces termed m, r and z; a nomenclature that is many years old - see "The Quartz Page". However the faces are individually calculated by the openSCAD code; any one or several can be enlarged with respect to the others simulating slow growth on one or a group of faces and forming more realistic and less perfect crystals. Rotate the crystal and place a large face on the build platform for printing.