I say mesh but am honestly not familiar with the fabric. Gathering at the back of neck. And ornate lapel with buttons with a few missing gems and missing belt. Any info would help.
Aww, sweet. This looks like a patterned leno weave (https://vintagefashionguild.org/fabric-resource/leno-weave/) to me. This looks like the sort of dress that would have been made in the 1950s or early 60s for a half size, and relating to some of the earlier trends. In other words, for a "older" woman with reminiscences of the past. I love this sort of thing.