There are dozens of different types of sheer fabrics, but there are a few that are most commonly used that I will discuss here.
Challis is a lightweight, plain-weave fabric that is made out of rayon, cotton or wool. I have seen both sheer and opaque challis. Darker colors tend to not appear as sheer as lighter colors. Challis drapes wonderfully and works well for dresses and blouses.
Crepe chiffon is a lightweight, sheer crepe that has a rougher, more matte surface than regular chiffon. It is a pain to sew because it slips and slides all over the place.
Eyelet is more of technique than an actual fabric type. An open-work design is embroidered on lightweight fabrics such as organdy or batiste. Depending on the base fabric, eyelet can be soft or crisp.
Georgette is a loosely woven double-sheer fabric made of silk or polyester. It is most similar in texture to crepe with a very soft hand.
Organdy is one of the more crisp fabrics in the family of sheers. It works very well for gathered or pleated garments because it poofs up nicely and has a lot of body. It does tend to wrinkle easily because it is made of a plain-weave cotton.
Organza is another plain-weave fabric that is woven from rayon, silk, or polyester. It is less crisp than organdy, but more so than chiffon.
Sheer fabrics can be used to construct entire garments or they can be used to add special detailing to a garment such as adding sheer sleeves to an opaque bodice. Transparent fabrics require some special treatment when being sewn because seams will show through and the fabrics can be delicate and prone to ripping and/or fraying.
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