Press F12 in game and file a bug report. It will allow you to attach screenshots so we can see the issue more clearly. If you let us know the EBR number (EVE Bug Report) here I can get it to our rendering engineers.
Please note that we are aware of some graphical defects in older macOS versions that have since been fixed (I don’t know what version you are running currently without an EBR). Due to the way drivers are updated on macOS, you may need to update the OS for these to be resolved.