Place where icons stored

Hi, please help answer me where are these KDE icons stored, I've searched web but no result. I'm aware of /usr/local/share/icons but there are plenty subfolders, I'd like to know where are these icons displayed on screenshot below (when 'other icons' selected).
I think 'other icons' are installed in /usr/local/share/pixmaps.

If not, you can run this to find e.g. the icon for assistant-qt4: find /usr/local/share/{icons,pixmaps} -iname 'assistant-qt4*'. There could be multiple results depending on how many icon themes you've installed and if there are multiple icon sizes available.