Unbranded Flowing Rayon Gown

[Autumn Sharma]

Hi there! I acquired this gown but cannot determine what era it belongs to. It has a back metal Lamar zip, buttons with a rhinestone in the middle, no pinking or surging and it's made of this fanatic rayon crepe fabric. Full and flowing silhouette.
Any ideas? I really want to identify it correctly.

Thanks so much for your help!
Autumn

 

[The Vintage Merchant]

first impression looks 70s to me.

 

[anothertimevintageapparel]

I agree with 1970s

 

[MagsRags]

That what I see too. Made by a talented home seamstress who used a metal zipper from her stash