Chemical diagrams are added using incorrect properties

[Former user]

Chemical diagrams in WD should be added either using P117 (structural formulae) or P8224 (3D models and crystal structures). P18 is used only for other images like photos of samples of chemical compounds.

In the past few months 2 users added thousands of files using WD-FIST to P18 that have to be manually corrected, in some cases deleted because of duplicates (explained in other ticket). It should be possible to add images using P117/P8224 or any additions to chemical compounds items should be blocked using this tool.