This is a wound overlay bead. The "heart" beads are drawn beads--such as "white-heart" and "green-heart" beads. The world would be a (slightly) less confusing place if people would not apply the names from one type of bead to another type of bead. A "yellow-heart" would be a drawn cornaline d'Aleppo with a yellow core layer and translucent red or reddish exterior.

I don't know of any wound overlay beads that have a "thin clear rose" exterior layer. Are you certain this is there (?); and are you certain it is glass and not something like a lacquer to make a dull bead shiny again—or something like that?

Among early drawn Venetian trade beads, there is a type that features a clear-white-clear layer sequence. They intitially appear to be white or grayish-white pony beads. However looking closely, you can see they have a clear exterior, that gives both a grayish cast to the color, and an enlarging/changing aspect to the look of the surface (because the clear glass acts as a magnifier). Occassionally, some early green-heart beads also have clear exteriors (translucent green-brickred-clear). Other than these, a clear glass exterior was not typical on most rounded drawn beads. With wound beads it's even more rare, because it would be a lot of work to make a very thin over-layer of glass onto a wound bead. It would be easier to make a thick overlayer (as with sommerso beads). So I would be surprised to think that your otherwise typical-looking Venetian overlay beads have this—as you propose. How did you determine this layer is there?

Jamey