What is this fabric called?

I have this gorgeous late 1920s dress and I need help identifying the name of the fabric. It is a silk satin, either crepe back, or charmeuse. It is quite light weight so I'm thinking charmeuse. It does burn test as pure silk. The fabric alternates between satin and a sheer stripe. Is there a specific name for this kind of alternating satin? It is not two different fabrics stitched together. The dress is weighted just below the drop waist at the seams. Attaching some photos of the fabric from both sides. Any thoughts on the name of this type of fabric would be appreciated!

 

Here are a few more of both sides of the fabric. This is the matching vest.

 

The fabric appears to be one single woven piece, I cannot identify a seam between the satin and chiffon stripes. I thought maybe this type of alternating stripe had a specific name. Here's the dress and details, it's a straight cut, drop waist, flares below the waist, attached low belt, smocking at the shoulders. The sleeves have a handkerchief cut that is tucked up under a rhinestone button. The neckline, cuffs, and hem, are all rolled and stitched by hand. It has a matching vest, but it is missing the original slip. I was thinking late 20s to very early 30s. It's definitely not the figure hugging, slim shape of typical 1930s.

 

I agree with MJ and see early '30s.

Lovely evening set, the large size is making it look like it's a drop-waist but on the right sized person it would show its true design. It's hard to display big dresses on small mannequins: their shape is distorted.

Thanks Maggie for piping in with the fabric! Yes, it's a silk satin stripe with chiffon: all one fabric and very nicely cut to get those godets in the skirt. Usually a different piece is cut for them but here they've just cleverly cut the striped fabric.