Custom Materials Not Allowing Same Appearance

[estringer]

I am adding/creating more custom materials for our company material library. I started by creating a duplicate of an existing one and then modifying the name and then changing the appearance, since most of them are the same material makeup but with a different appearance. On most of the ones that I have done so far, I have had to come up with alternate names for the material in order to get it to work but then on some others it will allow for the same material without revised naming. I can't find anything online that would indicate the why or why not of these occurrences. Does anyone have any experience with this? I find that Autodesk's documentation for custom material libraries is seriously lacking and there is very little information on how to proceed if this is done when using project files. As part of this, am I supposed to be using the Styles Editor to save or update these changes when I am done?

[Frederick_Law]

Don't use duplicate, ever.  It'll create a copy of material, physcial and appearance.

To "copy", add material to document.  Change the name and add it back to library.

This way it'll have different name but same physical and appearance.

[estringer]

We are adding the material to the document, right-click Duplicate, right-click Edit, right-click Add To XXX Library.