I have some pendants / lockets with one side pierced. I had not yet decided what to put inside when selling them: was going to use some of my own lavender. I recently saw some being sold as diffusers with essential oils. I think this is a better idea. The ones I saw had a small black felt disc inside.

Where do you get these inserts? I looked at felt in the craft store, but that was all a synthetic fabric that I don’t think would work well. The ones I saw offered for sale had a firm, stiffer feel: like they were cotton. But I have no
idea where to find the right fabric. I don’t mind cutting it to size: just want the right kind. Thanks!