Hi Frank, On Smorf, the website of Mark Holtkamp, this page will give you an idea of some of the plastic models available: https://www.smorf.nl/3dprints.php On the same page, towards the top, you'll see a link called "drawing". Going there, you can actually draw your own crystals, and export them as 3D-printable files. So if you want to make your own, all you'll need is a 3D-printer (or a good friend who has one). Cheers, Herwig https://www.mindat.org/user-86.html