The five confirmed fabrics
These five appear by name in the official Steam description. Everything else the shop stocks falls under "a wide range" — the complete list is Unconfirmed.
Cotton
Confirmed in the official description. Real-world character: the everyday workhorse — breathable, easy to sew, forgiving of mistakes. A sensible default for practice pieces and simple commissions.
Linen
Confirmed in the official description. Real-world character: crisp, cool and structured, with a tendency to crease. Reads as summery and relaxed rather than formal.
Wool
Confirmed in the official description. Real-world character: warm, weighty and drapey — the cold-weather staple that holds a silhouette well.
Silk
Confirmed in the official description. Real-world character: lustrous, fluid and slippery to work with — the classic luxury fabric for occasion wear.
Velvet
Confirmed in the official description. Real-world character: plush, deep and dramatic, with a pile that catches light. Reads as eveningwear and grandeur.
Real-world character — in-game role unconfirmed
Beyond the five
The store page promises a "wide range" of purchasable fabrics, so cotton, linen, wool, silk and velvet are not the whole shelf. No official source publishes the full list, per-fabric prices or stats — until one does, every additional fabric and every number is Unconfirmed here.
Decorations: the confirmed four
The official description names four decoration types and states that placement is completely free — there is no fixed slot grid.
Buttons
Officially confirmed. Functional or purely decorative closures, placed wherever you like on the garment.
Bows
Officially confirmed. Soft statement pieces — waist, neckline, hem; the choice is yours.
Appliqué
Officially confirmed. Fabric motifs layered onto the dress; the sketchbook lets you pin appliqué ideas before you commit.
Lace trims
Officially confirmed. Edging for hems, sleeves and necklines — and the achievement Trim and Proper asks for more than 50m of trim on a single dress, so lace can go a long way.