This item, known better by it’s English name partlet among many costumers, is what a modern person might refer to as a ‘dickie’. Among the lower classes it would likely have been linen (or possibly wool) and worn for practical purposes.
The story goes that the upper classes often wore them in response to sumptuary laws that determined their necklines must not be below a certain level. With a fazzoletto they could have their gamurra neckline as low as they liked and used a sheer silk fazzoletto to bring their neckline in line with the rules while flaunting them at the same time.
You can see the fazzoletto worn either under the gamurra or over it in period art but you might need to look close– sometimes they are hard to spot.
This detail from Domenico Ghirlandaio’s 1475-1477 Annunciation of the Death of St. Fina shows lower class women wearing a simple cut of opaque fabric.
Leonardo Da Vinci’s Portrait of Ginevra Benci dated 1474 shows the fazzoletto worn tucked into the bodice.
This portrait by Ghirlandaio suggests that if the fazzoletto was worn over the gamurra bodice it was worn under the outer garment.
Domenico Ghirlandaio’s Portraitdated 1485 shows the fazzoletto was sometimes held closed with a pin or button.
Agnolo e Donnino del Mazziere’s Portrait of a Young Woman shows a very sheer fazzoletto over the bodice of the gamura.
Domenico Ghirlandaio’s Portrait of a Lady dated to 1490 also shows a sheer fazzoletto over the bodice.
Sebastiano Mainardi’s Portrait of a Woman also dated 1490 shows a thicker, but still sheer fazzoletto edged with a decorative stitch.
My pattern is below:
It’s not a pattern you can print and use, but hopefully it will help with the general shape.
I have only made one fazzoletto which I made in silk, and hemmed it with silk thread using a decorative stitch.