Foil Rayon Umbrella

That is a beautiful midi dress in a black or dark base color with a multi-color floral print.
Based on the information you provided (“Fabric: foil rayon”), it’s likely a Foil Print Rayon Dress. This type of fabric is popular because:
* Rayon is soft, breathable, and has a nice drape, making it comfortable for everyday wear.
* Foil Print refers to a printing technique where a metallic or shiny design (often gold or silver, though sometimes subtle) is applied to the fabric surface, giving the flowers a slight shimmer.
The dress style appears to be a fit and flare or A-line silhouette with short sleeves and a midi length, which is a versatile style for casual or semi-casual outings.