It will shine for milling 'Golden Lotus' which currently are un-millable however, for desecrated herbs which are from Sha-Touched herbs, it will not shine nor allow you to use the addon to mill them for some reason. I tested this across multiple computers as well as had multiple friends try it out and it seemed to not work for any of them.

Sha-Touched Herbs are objects not items. When you use the Sha-Touched Herbs you can get Desecrated Herb which are millable. I've recently updated xanMortarPestle and have added those to the list. You may want to upgrade. If you feel I've missed an herb, please do the following.

Go to wowhead.com, search for the item, example: Desecrated Herb
You will get a link like this on your browser
http://www.wowhead.com/item=89639

The number at the end is the itemid which I need to add to the list. So Desecrated Herb = 89639

Again I've recently upgrade this addon, so update and let me know if you still have the issue.